Question

Before winter arrives, many kinds of birds start to fly south. People often call it migration. How much do you know about migration? Why do only some birds migrate? How do birds know when to go south? Can they find their way?

Some birds fly south because they may die from hunger if they don't do that. The woodpecker(啄木鸟),for example, doesn't need to fly south because it can find something to eat in the bark(树皮) of the trees. But some birds eat grains(谷物). Their food disappears in winter, so they must fly south where food can still be found. But why don't they stay there forever? Perhaps they know if they stay in the south, they will eat up food there, too.

Birds seem to know when winter comes because they find that the days are getting shorter in winter. Once they leave from the north, the sun is really helpful. The sun is in different positions in the sky at different time of a day. Birds know the time of the day by watching the position of the sun. On long flights, most of the birds use stars to navigate(导航) their way.

The homing pigeon(信鸽) doesn't use the sun or the stars. Scientists believe that it uses the magnetic field(磁场) of the earth. One of the most amazing migrations is that of the tiny hummingbird(蜂鸟). It travels from Canada to Mexico—a long distance of over 3600 kilometers.

1.The underlined word “migration” in the first paragraph means________

A.looking for food B.practicing flying C.moving to another place

2.The birds which eat grains fly south in winter mainly because________

A.they like warm weather better.

B.they really need food.

C.it is one of their habits.

3.On long migration flights, most birds find their way with the help of________

A.the stars B.the magnetic field C.the sun

4.Which of the following is NOT TRUE according to the passage?

A.The woodpecker doesn't need migration.

B.Many birds migrate in the middle of winter.

C.The hummingbird can fly to Mexico for food in winter.

5.What is the main idea of the passage?

A.The different ways birds use to migrate.

B.The reasons why many birds migrate in winter.

C.The mystery(奥秘) of birds' migration.

Answer

1.C

2.B

3.A

4.B

5.C

【解析】

文章大意：本文主要讲述了鸟的迁徙。

1.词义猜测题。根据“Before winter arrives, many kinds of birds start to fly south. People often call it migration.” 在冬天来临之前，许多鸟开始向南飞。人们常称之为“迁徙”，第一段加下划线的“migration”一词是指搬到另一个地方，故答案为C。

2.细节理解题。根据文中“But some birds eat grains(谷物). Their food disappears in winter, so they must fly south where food can still be found. ”但是有些鸟吃谷物。他们的食物在冬天消失了，所以他们必须飞到仍然可以找到食物的南方去。可知，冬天吃谷物的鸟飞到南方主要是因为他们真的需要食物，故答案为B。

3.细节理解题。根据文中“On long flights, most of the birds use stars to navigate(导航) their way. ”在长途飞行中，大多数鸟用星星来导航。可知，故答案为A。

4.细节理解题。根据文中“The woodpecker(啄木鸟),for example, doesn't need to fly south because it can find something to eat in the bark(树皮) of the trees” 例如，啄木鸟（woodpecker）不需要向南飞，因为它可以在树的树皮中找到吃的东西。可知，A是正确的；根据文中“Before winter arrives, many kinds of birds start to fly south.” 在冬天来临之前，许多鸟开始向南飞。可知，B是错误的；根据文中“One of the most amazing migrations is that of the tiny hummingbird(蜂鸟). It travels from Canada to Mexico ”最令人惊奇的迁徙之一是小蜂鸟的迁徙。它从加拿大到墨西哥。可知，C是正确的。故答案为B。

5.主旨大意题。根据文章内容可知，本文主要讲述了鸟的迁徙。有些鸟向南飞，因为如果不这样做，它们可能会饿死。鸟类似乎知道冬天什么时候来，因为它们发现冬天的白天越来越短。在长途飞行中，大多数鸟用星星来导航。可知，这篇文章的主旨是鸟类迁徙之谜。故答案为C。