We know that many animals do not stay in _______ place.Birds,fish and other animals move from one pl

题目

We know that many animals do not stay in _______ place.Birds,fish and other animals move from one place to another at a certain time.They move for different reasons:most of them move to find food more easily,but some move to get away from places that are too crowded.
When cold weather comes,many birds move to warmer places to find food.Some fishes give birth in warm water and move to cold water to feed.The most famous migration is probably the migration of one kind of fish,which is called “salmon”.This fish is born in fresh water but it travels many miles to salt water.There it spends most of its life.When it is old,it returns to its birthplace in fresh water.Then it gives birth and dies there.In northern Europe,there is a kind of mouse.They leave their mountain home when it becomes too crowded.They move down to the low land.Sometimes they move all the way to the seaside,and many of them are killed when they fall into the sea.
Recently,scientists have studied the migration of a

答案

1.c
2.c
3.b
4.c
5.a
绝对没错误