Question

Have you ever heard an echo of your voice?

An echo is a reflected(反射)sound. Stand in a very large, empty hall with nothing on the walls. Then shout. The sounds you make will hit the walls and come back to you. The walls reflect the sounds. These reflected sounds are called “echoes”.

We can use reflected sound to make sound travel farther. Hold a watch about fifty centimeters from your ear. You cannot hear it. The sound of the watch travels a short way in all directions. It does not travel as far as your ear. You can make it travel to your ear by using a roll of cardboard(纸板筒).

Make the roll of cardboard about fifty centimeters long. Put one end over your ear and hold the watch at the other. Now you can hear the watch because the sound has not gone in all directions. It is reflected down the roll to your ear.

A megaphone(喇叭筒)works in the same way. It makes sound travel farther. It reflects the sound into a beam which can travel a long way. In the ship, the sailor uses the megaphone to make his voice travel. Without the megaphone, his voice cannot travel far.

We use reflected sound in many ways. We use it to measure the depth of the sea, for example. Among the animals, bats and whales use reflected sound to tell them where they are and what things are near them.

1.What is called “echo”?

A．Very loud voices.

B．Very loud voices that are made by man.

C．Very loud voices that are made by animals.

D．The sound that is made by man or animals comes back from some place.

2.We can hear our echoes if we     .

A．shout in a small room

B．shout in a large house full of things

C．shout in narrow valleys(山谷)

D．shout in the open air

3.Which is the right order of hearing our echo in a very large, empty hall?

a. We hear the reflected sound

b. The sound returns to us

c. The sound hits the walls

d. We make a sound

A．c, b, a, d          B．c, a, b, d           C．d, c, b, a           D．d, b, c, a

4.From the text we learn that __________ .

A．reflected sound is useful only to blind people

B．people haven’t made use of reflected sound yet

C．bats use reflected sound to fly and get food

D．whales don’t use reflected sound as they live in the sea

5.If you haven’t got a megaphone, ____ will help you to make your voice travel farther.

A．a long piece of wood                     B．a roll of cardboard

C．a thin thread                           D．a long piece of silk

Answer

1.D

2.C

3.C

4.C

5.B

【解析】

试题分析：这篇短文主要讲述了回声是如何形成的。

1.根据短文第一段描述，可知选D，由人或者动物制造的，从某地反射回来的生意。

2.根据第三段描述，可知回声只能在向一个方向传播时才能形成，故选C，在狭窄的山谷里面喊。

3.根据短文第一段描述，可知回声形成的步骤是，首先我们发出声音，然后声音撞到墙上，再然后声音返回我们，最后我们听到声音，故选C。

4.根据最后一段Among the animals, bats and whales use reflected sound to tell them where they are and what things are near them.描述，可知选C。

5.根据第二段You can make it travel to your ear by using a roll of cardboard(纸板筒).描述，可知选B。

考点：关于回声的说明文阅读