单选题The phrase “this element of the unknown” (Paragraph 3) refers to ______.A the extension of earthquake zonesB the percentage of earthquake occurrencesC when and where earthquakes may occurD what big damage earthquakes may cause

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth ' s crust（地壳）slide past each other. When these pieces slip , the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
dict how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however,ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than 84 percent of the
city's buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Big One will hit.It's just a mat-
ter of when.

Scientist will be able to predict the exact time of an earthquake soon.
A:Right
B:Wrong
C:Not mentioned

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth ' s crust（地壳）slide past each other. When these pieces slip , the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
dict how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however,ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than 84 percent of the
city's buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Big One will hit.It's just a mat-
ter of when.

The highest speed of fault ruptures in the 1906 quake was more than 3.5 kilometers per second.
A:Right
B:Wrong
C:Not mentioned

共用题干
第一篇

How to Do with Earthquake?

Ideally,people would like to know when an earthquake is going to happen and how bad it will
be.In both Japan and China,people have long believed that earthquakes can be forecast. In Japan, scientists have wired the Earth and sea to detect movements.The Chinese have traditionally watched animals and plants for warning signs of earthquakes.For example,the Chinese have noted that before an earthquake,hens' behavior changes一they refuse to enter their cages at night. They have also noticed that snakes come out of the ground to freeze to death and that dogs bark a lot,even normally quiet dogs.Before the Hanshin earthquake in Japan,there were reports of large schools of fish swimming near the surface of the water. Certain birds,like pigeons,also seemed to be especially noisy and were reported to be flying in unusual patterns before the earthquake.
Perhaps most interesting,and most easily measured,is a chemical change in ground water before a quake.Experimental data seem to indicate that the amount of radon(Rn)in the water under the surface of the Earth waxes before an earthquake.
People would also like to be able to prevent the great destruction of property caused by earthquakes.After all,most of the people who die in earthquakes are killed by falling buildings.Therefore,building structures that can withstand the power of earthquakes is a major concern.Steel seems to be the best material,but not if it is welded to form a rigid structure.
Many new structures are built with a new type of steel joint,an I-joint,which appears to be the most durable type of joint. These joints of steel can move without breaking. Also,to prevent property damage,architects now design buildings so that the building's columns and horizontal beams are of equal strength,and vertical support columns are inserted deep into solid soil.In addition,many new houses have relatively light roofs and strong walls.Concrete pillars for highway bridges that previously only had steel rods inside are now enclosed in steel.
Besides working to improve building structures,people in areas where earthquakes are common need to prepare for the possibility of a great earthquake.They should regularly check and reinforce their homes,place heavy objects in low positions,attach cupboards and cabinets to walls,and fasten doors so that they will not open accidentally during an earthquake.

According to the passage,the amount of radon(Rn)in the water may______before earthquake.
A:increase
B:reduce
C:not change
D:disappear

共用题干
Earthquake

1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.
2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.
3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.
4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.
5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.

Paragraph 2_______.
A:Earthquakes forecast
B:Historical records of earthquakes
C:Intensities of earthquakes
D:Cause of earthquakes
E:Indications of earthquakes
F: Damaging earthquakes

共用题干
Earthquake

1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.
2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.
3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.
4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.
5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.

Scientists have been working hard to warn people__________.
A:by the quake itself
B:not be prevented
C:to cause damage of property and loss of lives
D:of a possible earthquake
E:the unusual behaviors of some animals
F: the strange behaviors of human beings

共用题干
Earthquake

1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.
2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.
3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.
4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.
5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.

Not all damage during an earthquake is caused___________.
A:by the quake itself
B:not be prevented
C:to cause damage of property and loss of lives
D:of a possible earthquake
E:the unusual behaviors of some animals
F: the strange behaviors of human beings

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth'S crust（地壳）slide past each other.When these pieces slip,the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
diet how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however.ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than S4 percent of the
city’s buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Rig One will hit.It',just a mat-
ter of when.

A major earthquake striking San Francisco someday is inevitable.
A:Right
B:Wrong
C:Not mentioned

共用题干
Earthquake Insurance

1.Earthquake insurance is a form of homeowners' insurance which deals with damage caused by earthquakes.In regions where earthquakes are especially common,homeowners may be required to carry earthquake insurance,so that in the event of an earthquake,people rely less on government disaster funds and more on their own insurance policies.As a general rule,earthquake insurance is not a part of standard insurance policies,and it must be purchased separately.
2.Earthquakes can cause a variety of damage to a home,ranging from complete destruction to damage which causes the building to become structurally unsound.Indirect damage caused by neigh-boring collapses of structures and freeways can also occur,as can more bizarre forms of earthquake damage,like winding up with a car in the living room or a sinkhole in the back yard.Fires and flooding are also common problems in the wake of earthquakes.
3.When homeowners purchase earthquake insurance,they may be protected against both direct damage,such as a structural collapse after an earthquake,and indirect damage,like a fire caused by broken gas lines.More commonly,the insurance only covers structural damage caused directly by the earthquake.The insurance may pay for a complete replacement of the structure,or a remodel, depending on the type of insurance and the nature of the damage.Some policies also cover damaged property like cars,and they may provide living allowances so that the residents of the home can temporarily relocate for the duration of the repairs.
4.This type of homeowners' insurance is prone to adverse selection,in which only people in high risk areas purchase the insurance.The problem with adverse selection for insurance companies is that it decreases the pool of customers,making potential payouts very expensive.For this reason, earthquake insurance often has a high deductible,and it can he very expensive.
5.Recognizing the need for earthquake insurance,some governments have provided subsidies for earthquake insurance,to reduce the stress on insurance companies.Insurance companies also adjust their risk pools carefully,and there may be stringent requirements for a homeowner to purchase earthquake insurance.For example,a home may need to be retrofitted for earthquake safety, reducing the amount of damage which will be incurred in a quake.For low-income home owners, this can be very difficult,as it drives the cost of earthquake insurance out of reach,which can in turn make it difficult to get home loans,as many banks in earthquake-prone areas insist on earth-quake insurance as a condition for a loan.

Earthquakes can cause a variety of direct damage and______.
A:indirect damage
B:risk pools
C:government disaster funds
D:the nature of the damage
E:insurance policies
F: prices

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth'S crust（地壳）slide past each other.When these pieces slip,the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
diet how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however.ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than S4 percent of the
city’s buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Rig One will hit.It',just a mat-
ter of when.

Earthquakes rarely happened in San Francisco before 1906.
A:Right
B:Wrong
C:Not mentioned

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth'S crust（地壳）slide past each other.When these pieces slip,the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
diet how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however.ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than S4 percent of the
city’s buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Rig One will hit.It',just a mat-
ter of when.

San Francisco is fully prepared br another big earthquake.
A:Right
B:Wrong
C:Not mentioned

共用题干
Earthquake Insurance

1.Earthquake insurance is a form of homeowners' insurance which deals with damage caused by earthquakes.In regions where earthquakes are especially common,homeowners may be required to carry earthquake insurance,so that in the event of an earthquake,people rely less on government disaster funds and more on their own insurance policies.As a general rule,earthquake insurance is not a part of standard insurance policies,and it must be purchased separately.
2.Earthquakes can cause a variety of damage to a home,ranging from complete destruction to damage which causes the building to become structurally unsound.Indirect damage caused by neigh-boring collapses of structures and freeways can also occur,as can more bizarre forms of earthquake damage,like winding up with a car in the living room or a sinkhole in the back yard.Fires and flooding are also common problems in the wake of earthquakes.
3.When homeowners purchase earthquake insurance,they may be protected against both direct damage,such as a structural collapse after an earthquake,and indirect damage,like a fire caused by broken gas lines.More commonly,the insurance only covers structural damage caused directly by the earthquake.The insurance may pay for a complete replacement of the structure,or a remodel, depending on the type of insurance and the nature of the damage.Some policies also cover damaged property like cars,and they may provide living allowances so that the residents of the home can temporarily relocate for the duration of the repairs.
4.This type of homeowners' insurance is prone to adverse selection,in which only people in high risk areas purchase the insurance.The problem with adverse selection for insurance companies is that it decreases the pool of customers,making potential payouts very expensive.For this reason, earthquake insurance often has a high deductible,and it can he very expensive.
5.Recognizing the need for earthquake insurance,some governments have provided subsidies for earthquake insurance,to reduce the stress on insurance companies.Insurance companies also adjust their risk pools carefully,and there may be stringent requirements for a homeowner to purchase earthquake insurance.For example,a home may need to be retrofitted for earthquake safety, reducing the amount of damage which will be incurred in a quake.For low-income home owners, this can be very difficult,as it drives the cost of earthquake insurance out of reach,which can in turn make it difficult to get home loans,as many banks in earthquake-prone areas insist on earth-quake insurance as a condition for a loan.

Insurance companies also adjust their______.
A:indirect damage
B:risk pools
C:government disaster funds
D:the nature of the damage
E:insurance policies
F: prices

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth ' s crust（地壳）slide past each other. When these pieces slip , the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
dict how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however,ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than 84 percent of the
city's buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Big One will hit.It's just a mat-
ter of when.

Earthquakes rarely happened in San Francisco before 1906.
A:Right
B:Wrong
C:Not mentioned

共用题干
A Great Quake Coming?

Everyone who lives in San Francisco knows that earthquakes are common in the Bay Area一and they
can be devastating. In 1906,for example,a major quake destroyed about 28,000 buildings and killed
hundreds,perhaps thousands of people.Residents now wonder when the next"Big One"will strike.It's
bound to happen someday. At least seven active fault（断层）lines run through the San Francisco area. Faults
are places where pieces of Earth ' s crust（地壳）slide past each other. When these pieces slip , the ground
shakes.
To prepare for that day,scientists are using new techniques to reanalyze the 1906 earthquake and pre-
dict how bad the damage might be when the next one happens.
One new finding about the 1906 earthquake is that the San Andreas fault split apart faster than scientists
had assumed at the time. During small earthquakes,faults rupture（断裂）at about 2.7 kilometers per second.
During bigger quakes,however,ruptures can happen at rates faster than 3.5 kilometers per second.
At such high speeds,massive amounts of pressure build up,generating underground waves that can
cause more damage than the quake itself. Lucky for San Francisco , these pressure pulses（脉冲）traveled
away from the city during the 1906 event.As bad as the damage was,it could have been far worse.
Looking ahead,scientists are trying to predict when the next major quake will occur. Records show that
earthquakes were common before 1906.Since then,the area has been relatively quiet.Patterns in the data,
however,suggest that the probability of a major earthquake striking the Bay Area before 2032 is at least 62
percent.
New buildings in San Francisco are quite safe in case of future quakes.Still,more than 84 percent of the
city's buildings are old and weak.Analyses suggest that another massive earthquake would cause extensive
damage.
People who live there today tend to feel safe because San Francisco has remained pretty quiet for a
while.According to the new research,however,it's not a matter of"if" the Big One will hit.It's just a mat-
ter of when.

San Francisco is fully prepared for another big earthquake.
A:Right
B:Wrong
C:Not mentioned

共用题干
第一篇

How to Do with Earthquake?

Ideally,people would like to know when an earthquake is going to happen and how bad it will
be.In both Japan and China,people have long believed that earthquakes can be forecast. In Japan, scientists have wired the Earth and sea to detect movements.The Chinese have traditionally watched animals and plants for warning signs of earthquakes.For example,the Chinese have noted that before an earthquake,hens' behavior changes一they refuse to enter their cages at night. They have also noticed that snakes come out of the ground to freeze to death and that dogs bark a lot,even normally quiet dogs.Before the Hanshin earthquake in Japan,there were reports of large schools of fish swimming near the surface of the water. Certain birds,like pigeons,also seemed to be especially noisy and were reported to be flying in unusual patterns before the earthquake.
Perhaps most interesting,and most easily measured,is a chemical change in ground water before a quake.Experimental data seem to indicate that the amount of radon(Rn)in the water under the surface of the Earth waxes before an earthquake.
People would also like to be able to prevent the great destruction of property caused by earthquakes.After all,most of the people who die in earthquakes are killed by falling buildings.Therefore,building structures that can withstand the power of earthquakes is a major concern.Steel seems to be the best material,but not if it is welded to form a rigid structure.
Many new structures are built with a new type of steel joint,an I-joint,which appears to be the most durable type of joint. These joints of steel can move without breaking. Also,to prevent property damage,architects now design buildings so that the building's columns and horizontal beams are of equal strength,and vertical support columns are inserted deep into solid soil.In addition,many new houses have relatively light roofs and strong walls.Concrete pillars for highway bridges that previously only had steel rods inside are now enclosed in steel.
Besides working to improve building structures,people in areas where earthquakes are common need to prepare for the possibility of a great earthquake.They should regularly check and reinforce their homes,place heavy objects in low positions,attach cupboards and cabinets to walls,and fasten doors so that they will not open accidentally during an earthquake.

What should people do to prepare for earthquakes?
A:Check and reinforce their homes.
B:Place light objects in low positions.
C:Build strong roofs and light walls.
D:Attach doors to walls.

共用题干
Earthquake

1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.
2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.
3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.
4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.
5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.

Earthquakes can be predicted by observing__________.
A:by the quake itself
B:not be prevented
C:to cause damage of property and loss of lives
D:of a possible earthquake
E:the unusual behaviors of some animals
F: the strange behaviors of human beings

共用题干
Earthquake

1.Every year earthquakes are responsible for a large number of deaths and a vast amount of destruction in various parts of the world.Most of these damaging earthquakes occur either in a narrow belt which surrounds the Pacific Ocean or in a line which extends from Burma to the Alps in Europe. Some of the destruction is directly caused by the quake itself. An example of this is the collapse of buildings as a result of the quake itself. Other damage results from landslides or major fires which are initiated by the quake.
2.There are about a million quakes a year. Fortunately,however,not all of them are destructive.The intensity of an earthquake is measured on the Richter Scale,which goes from 0 upward. The highest scale recorded to date is 8.9.Major damage generally occurs from quakes ranging upwards from 6.0.
3.The actual cause of the quake itself is the breaking of rocks at or below the earth's surface. This is produced by pressure which scientists believe may be due to a number of reasons, two of which are the expansion and contraction of the earth's crust and continental drift.
4.In order to limit the damage and to prevent some of the suffering resulting from earthquakes, scientists are working on ways to enable accurate prediction.Special instruments are used to help people record,for example,shaking of the earth.Scientists are trying to find methods that will enable them to indicate the exact time,location and size of an earthquake.
5.Certain phenomena have been observed which are believed to be signs of imminent earth-quakes.These include strange behaviors of some animals,the changes in the content of mineral water,etc.The magnetic properties of rocks may also display special pattern before major earthquakes happen.

Paragraph 3_________.
A:Earthquakes forecast
B:Historical records of earthquakes
C:Intensities of earthquakes
D:Cause of earthquakes
E:Indications of earthquakes
F: Damaging earthquakes

共用题干
Earthquake Insurance

1.Earthquake insurance is a form of homeowners' insurance which deals with damage caused by earthquakes.In regions where earthquakes are especially common,homeowners may be required to carry earthquake insurance,so that in the event of an earthquake,people rely less on government disaster funds and more on their own insurance policies.As a general rule,earthquake insurance is not a part of standard insurance policies,and it must be purchased separately.
2.Earthquakes can cause a variety of damage to a home,ranging from complete destruction to damage which causes the building to become structurally unsound.Indirect damage caused by neigh-boring collapses of structures and freeways can also occur,as can more bizarre forms of earthquake damage,like winding up with a car in the living room or a sinkhole in the back yard.Fires and flooding are also common problems in the wake of earthquakes.
3.When homeowners purchase earthquake insurance,they may be protected against both direct damage,such as a structural collapse after an earthquake,and indirect damage,like a fire caused by broken gas lines.More commonly,the insurance only covers structural damage caused directly by the earthquake.The insurance may pay for a complete replacement of the structure,or a remodel, depending on the type of insurance and the nature of the damage.Some policies also cover damaged property like cars,and they may provide living allowances so that the residents of the home can temporarily relocate for the duration of the repairs.
4.This type of homeowners' insurance is prone to adverse selection,in which only people in high risk areas purchase the insurance.The problem with adverse selection for insurance companies is that it decreases the pool of customers,making potential payouts very expensive.For this reason, earthquake insurance often has a high deductible,and it can he very expensive.
5.Recognizing the need for earthquake insurance,some governments have provided subsidies for earthquake insurance,to reduce the stress on insurance companies.Insurance companies also adjust their risk pools carefully,and there may be stringent requirements for a homeowner to purchase earthquake insurance.For example,a home may need to be retrofitted for earthquake safety, reducing the amount of damage which will be incurred in a quake.For low-income home owners, this can be very difficult,as it drives the cost of earthquake insurance out of reach,which can in turn make it difficult to get home loans,as many banks in earthquake-prone areas insist on earth-quake insurance as a condition for a loan.

Paragraph 3______
A:What's the Main Problem of Earthquake Insurance?
B:What Damages Can an Earthquake Cause?
C:How to Buy an Earthquake Insurance?
D:What Is an Earthquake Insurance?
E:Where Does Earthquake Happen Frequently?
F: What Does an Earthquake Insurance Contain?

共用题干
Earthquake Insurance

1.Earthquake insurance is a form of homeowners' insurance which deals with damage caused by earthquakes.In regions where earthquakes are especially common,homeowners may be required to carry earthquake insurance,so that in the event of an earthquake,people rely less on government disaster funds and more on their own insurance policies.As a general rule,earthquake insurance is not a part of standard insurance policies,and it must be purchased separately.
2.Earthquakes can cause a variety of damage to a home,ranging from complete destruction to damage which causes the building to become structurally unsound.Indirect damage caused by neigh-boring collapses of structures and freeways can also occur,as can more bizarre forms of earthquake damage,like winding up with a car in the living room or a sinkhole in the back yard.Fires and flooding are also common problems in the wake of earthquakes.
3.When homeowners purchase earthquake insurance,they may be protected against both direct damage,such as a structural collapse after an earthquake,and indirect damage,like a fire caused by broken gas lines.More commonly,the insurance only covers structural damage caused directly by the earthquake.The insurance may pay for a complete replacement of the structure,or a remodel, depending on the type of insurance and the nature of the damage.Some policies also cover damaged property like cars,and they may provide living allowances so that the residents of the home can temporarily relocate for the duration of the repairs.
4.This type of homeowners' insurance is prone to adverse selection,in which only people in high risk areas purchase the insurance.The problem with adverse selection for insurance companies is that it decreases the pool of customers,making potential payouts very expensive.For this reason, earthquake insurance often has a high deductible,and it can he very expensive.
5.Recognizing the need for earthquake insurance,some governments have provided subsidies for earthquake insurance,to reduce the stress on insurance companies.Insurance companies also adjust their risk pools carefully,and there may be stringent requirements for a homeowner to purchase earthquake insurance.For example,a home may need to be retrofitted for earthquake safety, reducing the amount of damage which will be incurred in a quake.For low-income home owners, this can be very difficult,as it drives the cost of earthquake insurance out of reach,which can in turn make it difficult to get home loans,as many banks in earthquake-prone areas insist on earth-quake insurance as a condition for a loan.

Paragraph 4______
A:What's the Main Problem of Earthquake Insurance?
B:What Damages Can an Earthquake Cause?
C:How to Buy an Earthquake Insurance?
D:What Is an Earthquake Insurance?
E:Where Does Earthquake Happen Frequently?
F: What Does an Earthquake Insurance Contain?

共用题干
Earthquake Insurance

1.Earthquake insurance is a form of homeowners' insurance which deals with damage caused by earthquakes.In regions where earthquakes are especially common,homeowners may be required to carry earthquake insurance,so that in the event of an earthquake,people rely less on government disaster funds and more on their own insurance policies.As a general rule,earthquake insurance is not a part of standard insurance policies,and it must be purchased separately.
2.Earthquakes can cause a variety of damage to a home,ranging from complete destruction to damage which causes the building to become structurally unsound.Indirect damage caused by neigh-boring collapses of structures and freeways can also occur,as can more bizarre forms of earthquake damage,like winding up with a car in the living room or a sinkhole in the back yard.Fires and flooding are also common problems in the wake of earthquakes.
3.When homeowners purchase earthquake insurance,they may be protected against both direct damage,such as a structural collapse after an earthquake,and indirect damage,like a fire caused by broken gas lines.More commonly,the insurance only covers structural damage caused directly by the earthquake.The insurance may pay for a complete replacement of the structure,or a remodel, depending on the type of insurance and the nature of the damage.Some policies also cover damaged property like cars,and they may provide living allowances so that the residents of the home can temporarily relocate for the duration of the repairs.
4.This type of homeowners' insurance is prone to adverse selection,in which only people in high risk areas purchase the insurance.The problem with adverse selection for insurance companies is that it decreases the pool of customers,making potential payouts very expensive.For this reason, earthquake insurance often has a high deductible,and it can he very expensive.
5.Recognizing the need for earthquake insurance,some governments have provided subsidies for earthquake insurance,to reduce the stress on insurance companies.Insurance companies also adjust their risk pools carefully,and there may be stringent requirements for a homeowner to purchase earthquake insurance.For example,a home may need to be retrofitted for earthquake safety, reducing the amount of damage which will be incurred in a quake.For low-income home owners, this can be very difficult,as it drives the cost of earthquake insurance out of reach,which can in turn make it difficult to get home loans,as many banks in earthquake-prone areas insist on earth-quake insurance as a condition for a loan.

The insurance paid for earthquake depends on the type of insurance and______.
A:indirect damage
B:risk pools
C:government disaster funds
D:the nature of the damage
E:insurance policies
F: prices

共用题干
Earthquake Insurance

1.Earthquake insurance is a form of homeowners' insurance which deals with damage caused by earthquakes.In regions where earthquakes are especially common,homeowners may be required to carry earthquake insurance,so that in the event of an earthquake,people rely less on government disaster funds and more on their own insurance policies.As a general rule,earthquake insurance is not a part of standard insurance policies,and it must be purchased separately.
2.Earthquakes can cause a variety of damage to a home,ranging from complete destruction to damage which causes the building to become structurally unsound.Indirect damage caused by neigh-boring collapses of structures and freeways can also occur,as can more bizarre forms of earthquake damage,like winding up with a car in the living room or a sinkhole in the back yard.Fires and flooding are also common problems in the wake of earthquakes.
3.When homeowners purchase earthquake insurance,they may be protected against both direct damage,such as a structural collapse after an earthquake,and indirect damage,like a fire caused by broken gas lines.More commonly,the insurance only covers structural damage caused directly by the earthquake.The insurance may pay for a complete replacement of the structure,or a remodel, depending on the type of insurance and the nature of the damage.Some policies also cover damaged property like cars,and they may provide living allowances so that the residents of the home can temporarily relocate for the duration of the repairs.
4.This type of homeowners' insurance is prone to adverse selection,in which only people in high risk areas purchase the insurance.The problem with adverse selection for insurance companies is that it decreases the pool of customers,making potential payouts very expensive.For this reason, earthquake insurance often has a high deductible,and it can he very expensive.
5.Recognizing the need for earthquake insurance,some governments have provided subsidies for earthquake insurance,to reduce the stress on insurance companies.Insurance companies also adjust their risk pools carefully,and there may be stringent requirements for a homeowner to purchase earthquake insurance.For example,a home may need to be retrofitted for earthquake safety, reducing the amount of damage which will be incurred in a quake.For low-income home owners, this can be very difficult,as it drives the cost of earthquake insurance out of reach,which can in turn make it difficult to get home loans,as many banks in earthquake-prone areas insist on earth-quake insurance as a condition for a loan.

In regions where earthquakes are especially common,people rely more on______.
A:indirect damage
B:risk pools
C:government disaster funds
D:the nature of the damage
E:insurance policies
F: prices

共用题干
Earthquake

How does an earthquake start?
What makes an earthquake happen? The rock of the earth's crust（地壳）may have a
"fault",a kind of break in the surface.The blocks which make up the earth move,and
sometimes this may cause the sides of the fault to move up and down or lengthways（纵向
地）against each other. When one piece of rock starts to rub on another with great force,a
lot of energy is used. This energy is changed into vibrations（振动）and it is these vibrations
that we feel as an earthquake.The vibrations can travel thousands of kilometers and so an
earthquake in Turkey may be felt in Greece.
What to do during an earthquake?
At school
As soon as the earthquake starts,students should get under the desks immediately and
wait until the teacher tells them it is safe to come out.The teacher should,at the same
time, go immediately to the teacher's desk, get underneath（在……下面）it and stay there
till the danger is over. Students must not argue with the teacher or question instructions.
As soon as the tremors（震动）stop, all students should walk towards the exit and go
straight to the school playground or any open space such as a square or a park.They must
wait there until the teacher tells them it is safe to go.
At home
If you are at home when the earthquake occurs,get immediately under the table in the
living room or kitchen.Choose the biggest and strongest table you can find.You must not
go anywhere near the window and don't go out onto the balcony（阳台）.Once the tremors
have stopped,you can come out from under the table but you must leave the building
straight away.You should walk down the stairs and should not use the lift一there may be a
power cut as a result of the earthquake and you could find yourself trapped inside the lift for
hours.
In the street
If you are in the street when the earthquake takes place,do not stand near buildings,
fences or walls一move away as quickly as possible and try to find a large open space to wait
in.Standing under trees could also be dangerous.

If you are at home when an earthquake occurs,stand near a big table.
A:Right
B:Wrong
C:Not mentioned