共用题干Operation MigrationIf you look up at the sky in the early fall in the northern part of North America,you may see groups of birds.These birds are flying south to places where they can find food and warmth for the winter.They are migrating（迁徙）.The young birds usually learn to migrate from their parents.They follow their parents south.In one unusual case,however,the young birds are following something very different.These birds are young whooping cranes,and they are following an airplane!The whooping crane is the largest bird that is native to North America.These birds al-most disappeared in the 1800s.By 1941,there were only about 20 cranes alive.In the 1970s, people were worried that these creatures were in danger of disappearing completely.As a result,the United States indentified whooping cranes as an endangered species that they needed to protect.Some researchers tried to help.They began to breed whooping cranes in special parks to increase the number of birds.This plan was successful.There were a lot of new baby birds.As the birds became older,the researchers wanted to return them to nature.However,there was a problem:These young birds did not know how to migrate.They needed human help.In 2001,some people had a creative idea.They formed an organization called Operation Migration.This group decided to use very light airplanes,instead of birds,to lead the young whooping cranes on their first trip south.They painted each airplane to look like a whooping crane.Even the pilots wore special clothing to make them look like cranes.The cranes began to trust the airplanes,and the plan worked.Today,planes still lead birds across approximately 1,200 miles(1,931 kilometers), from the United States-Canadian border to the Gulf of Mexico.They leave the birds at differ-ent sites.If a trip is successful,the birds can travel on their own in the future.Then,when these birds become parents,they will teach their young to migrate.The people of Operation Migration think this is the only way to maintain the whooping crane population.Operation Migration works with several other organizations and government institutes.Together,they assist hundreds of cranes each year.However,some experts predict that soon,this won't be necessary.Thanks to Operation Migration and its partners,the crane population will continue to migrate.Hopefully,they won't need human help any more.If operation Migration is successful,whooping cranes will______.A:learn to migrate on their ownB:follow airplanes south every yearC:live in Canada all year roundD:be unable to fly back
共用题干
Operation Migration
If you look up at the sky in the early fall in the northern part of North America,you may see groups of birds.These birds are flying south to places where they can find food and warmth for the winter.They are migrating（迁徙）.The young birds usually learn to migrate from their parents.They follow their parents south.In one unusual case,however,the young birds are following something very different.These birds are young whooping cranes,and they are following an airplane!
The whooping crane is the largest bird that is native to North America.These birds al-most disappeared in the 1800s.By 1941,there were only about 20 cranes alive.In the 1970s, people were worried that these creatures were in danger of disappearing completely.As a result,the United States indentified whooping cranes as an endangered species that they needed to protect.
Some researchers tried to help.They began to breed whooping cranes in special parks to increase the number of birds.This plan was successful.There were a lot of new baby birds.As the birds became older,the researchers wanted to return them to nature.However,there was a problem:These young birds did not know how to migrate.They needed human help.
In 2001,some people had a creative idea.They formed an organization called Operation Migration.This group decided to use very light airplanes,instead of birds,to lead the young whooping cranes on their first trip south.They painted each airplane to look like a whooping crane.Even the pilots wore special clothing to make them look like cranes.The cranes began to trust the airplanes,and the plan worked.
Today,planes still lead birds across approximately 1,200 miles(1,931 kilometers), from the United States-Canadian border to the Gulf of Mexico.They leave the birds at differ-ent sites.If a trip is successful,the birds can travel on their own in the future.Then,when these birds become parents,they will teach their young to migrate.The people of Operation Migration think this is the only way to maintain the whooping crane population.
Operation Migration works with several other organizations and government institutes.Together,they assist hundreds of cranes each year.However,some experts predict that soon,this won't be necessary.Thanks to Operation Migration and its partners,the crane population will continue to migrate.Hopefully,they won't need human help any more.
Operation Migration
If you look up at the sky in the early fall in the northern part of North America,you may see groups of birds.These birds are flying south to places where they can find food and warmth for the winter.They are migrating（迁徙）.The young birds usually learn to migrate from their parents.They follow their parents south.In one unusual case,however,the young birds are following something very different.These birds are young whooping cranes,and they are following an airplane!
The whooping crane is the largest bird that is native to North America.These birds al-most disappeared in the 1800s.By 1941,there were only about 20 cranes alive.In the 1970s, people were worried that these creatures were in danger of disappearing completely.As a result,the United States indentified whooping cranes as an endangered species that they needed to protect.
Some researchers tried to help.They began to breed whooping cranes in special parks to increase the number of birds.This plan was successful.There were a lot of new baby birds.As the birds became older,the researchers wanted to return them to nature.However,there was a problem:These young birds did not know how to migrate.They needed human help.
In 2001,some people had a creative idea.They formed an organization called Operation Migration.This group decided to use very light airplanes,instead of birds,to lead the young whooping cranes on their first trip south.They painted each airplane to look like a whooping crane.Even the pilots wore special clothing to make them look like cranes.The cranes began to trust the airplanes,and the plan worked.
Today,planes still lead birds across approximately 1,200 miles(1,931 kilometers), from the United States-Canadian border to the Gulf of Mexico.They leave the birds at differ-ent sites.If a trip is successful,the birds can travel on their own in the future.Then,when these birds become parents,they will teach their young to migrate.The people of Operation Migration think this is the only way to maintain the whooping crane population.
Operation Migration works with several other organizations and government institutes.Together,they assist hundreds of cranes each year.However,some experts predict that soon,this won't be necessary.Thanks to Operation Migration and its partners,the crane population will continue to migrate.Hopefully,they won't need human help any more.
If operation Migration is successful,whooping cranes will______.
A:learn to migrate on their own
B:follow airplanes south every year
C:live in Canada all year round
D:be unable to fly back
A:learn to migrate on their own
B:follow airplanes south every year
C:live in Canada all year round
D:be unable to fly back
参考解析
解析：题干意为“美洲鹤在冬天迁徒以寻找温暖的气候与食物。”短文第一段第二句提到“这些鸟飞到南部一些地方，在那里它们可以找到食物并温暖的过冬”，故选A。
题干意为“美洲鹤原产于北美洲。”短文第二段第一句提到“美洲鹤是原产于北美洲最大的鸟类”，故选A。
题干意为“操作迁徒的目的是引导幼鹤首次南迁。”短文第四段第三句提到“这个组织决定用一些轻型飞机，而不是鸟，来引导这些年幼的美洲鹤首次南迁”，故选C。
题干意为“这些年幼的美洲鹤南迁需要跨越的距离是1200英里。”短文第五段第一句提到“现在，飞机仍然引导鸟儿跨越约1200英里”，故此选C。
题干意为“如果操作迁徒成功，美洲鹤将学会自己迁徒。”短文第五段第三句提到“如果旅途成功，在未来这些鸟将学会自己旅行”，故此选A。
题干意为“美洲鹤原产于北美洲。”短文第二段第一句提到“美洲鹤是原产于北美洲最大的鸟类”，故选A。
题干意为“操作迁徒的目的是引导幼鹤首次南迁。”短文第四段第三句提到“这个组织决定用一些轻型飞机，而不是鸟，来引导这些年幼的美洲鹤首次南迁”，故选C。
题干意为“这些年幼的美洲鹤南迁需要跨越的距离是1200英里。”短文第五段第一句提到“现在，飞机仍然引导鸟儿跨越约1200英里”，故此选C。
题干意为“如果操作迁徒成功，美洲鹤将学会自己迁徒。”短文第五段第三句提到“如果旅途成功，在未来这些鸟将学会自己旅行”，故此选A。