We know that many animals do not stay ill one 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 others move to get away from places that are too crowed.
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 (迁移) is probably the migration of the fish, which is called “salmon”(麻哈鱼). This fish is born in fresh water but it travels many miles to salt water. There it spends its life. When it is cold, 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 homes when they become 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 kind lobster (龙虾). Every year, when the season of bad weather arrives, the lobster get into a long time and start to walk across tile floor of the ocean. Nobody knows why they do this, and nobody knows where they go.
So, sometimes we know why humans and animals move from one place to another, but at other times we don’t. Maybe living things just like to travel.
根据材料内容选择最佳答案,将其标号填入题前括号内。
Most animals move from one place to another at a certain time to _______.
A.give birth | B.enjoy warmer weather |
C.find food more easily | D.find beautiful places |
The fish called “salmon” spends a long life in_______.
A.salt water | B.rivers |
C.fresh water | D.its birthplace |
The mice in northern Europe leave their mountain when _______.
A.they give birth | B.the weather is bad |
C.the place get too crowded | D.they haven’t enough food |
The lobster move_______.
A.to the fresh water | B.to the sea floor |
C.at a certain time | D.to find more food |
What is the main idea of the passage?
A.Animals move in order to find food more easily. |
B.The migration of the fish called “Salmon” is the most famous migration. |
C.Living things move from one place to another because they like to travel. |
D.Sometimes we know why and how living things move from one place to another, but sometimes we don’t. |