阅读理解。

     Bats are the only "flying animals" in the world. They can't see very well. We often hear "as blind as

a bat". Yet they have no trouble flying on the darkest nights and finding their ways round. How can

bats fly and see at night? They fly by radar(雷达).

     The bat's radar system(系统) works the same way as the radar in ships and planes. As a bat flies

through the air, it makes a sound. If the sound hits things, it will come back and the bat's ears will

receive the message. In this way the bat is able to know where the things are.

     Bats go out for food at night. In the daytime they hang in some dark places. Some people think

bats are bad animals. In fact they are useful animals.

1. We call bats "flying animals" because __________ .

A. they have the radar system

B. they look for food at night

C. they are animals, but they can fly

D. they are useful animals

2. As __________,bats can easily find food on the darkest nights.

A. they can see everything all the time

B. they can "hear" everything around them

C. they have good eyesight

D. they can only fly to the places where they live

3. Bats make a sound so that __________.

A. they can know where the things are

B. they can find their friends

C. they try to tell their friends where they are

D. their "food" can fly to them

4. From the passage, we know __________.

A. bats are also birds

B. bats like singing

C. bats' ears are more useful than their eyes

D. what bats' favorite food is

5. Which of the following is the best title of the passage?

A. Why Bats Fly at Night

B. The Flying Animal

C. Animals or Birds

D. The Animal With the Radar System