Question

    Something makes your throat strange. It night be a piece of dust or some food that went down your breathing tube by mistake or mucus(黏液）that dropped down from your nose. You cough.

Sometimes you cough on purpose because you want to clear your throat. Other times you don't have to cough. Cough are useful. They clear your main breathing tube, the same way you clear a straw when you blow through it.

If you have mucus or dust or food in your throat, a cough will help to clear it out. But if you have an infection, a cough won't make it go away. That's why, sometimes, you keep coughing. If you do a lot of coughing, your stomach and chest muscles might ache from extra exercise.

Every cough happens in the same way: Firstly, you take a breath so that you have air in your lungs. Secondly, you close your throat and tighten up some of the muscles in your chest, getting them ready for the big push.

Coughs make an exploding sound because of the air that is pushed out of your lungs through closed lips in the back of your throat. These vocal cords(声带)are forced open by the air causing the explosion that we call a cough. They are the same vocal cords that make the noise when you sing or talk; you sound like you because of your vocal cords.

You can tell who is talking by the sound of a person's voice, but it's hard to tell who is coughing by the sound of the cough. People with high voices sometimes have low coughs. People with low voices sometimes have high coughs. That's because the sound of a cough depends upon how much air is blown out and whether or not the vocal cords are swollen from an infection.

1.What is the first step of a cough?

A. Sending out air. B. Breathing in air.

C. Opening the mouth. D. Closing your throat.

2.What can we learn from the text?

A. Coughs are bad for one's health.

B. Coughs can cure an infection.

C. A lot of coughs can make your chest muscles ache.

D. People with high voices always have high coughs.

3.What is the main function of cough?

A. Clearing your throat. B. Cleaning your nose.

C. Preparing for singing a song. D. Making an exploding sound.

4.What makes the sound of a cough different?

A. Throat. B. Breathing tubes.

C. The amount of air blown out. D. The voices of people.

Answer

1.B

2.C

3.A

4.C

【解析】

本文属于科普文，介绍咳嗽的背后的一些原理和知识。

1.细节理解题。根据第四段Every cough happens in the same way: Firstly, you take a breath so that you have air in your lungs可知，咳嗽的第一步，把空气吸入肺部，故选B。

2.推理判断题。根据第三段If you do a lot of coughing, your stomach and chest muscles might ache from extra exercise.可知，咳嗽过多，腹部和胸部肌肉会因为运动过多而疼痛，故选C。

3.细节理解题。根据第二段Sometimes you cough on purpose because you want to clear your throat.可知，咳嗽主要是为了清理喉咙上的异物，故选A。

4.细节理解题。根据最后一段That's because the sound of a cough depends upon how much air is blown out and whether or not the vocal cords are swollen from an infection.可知，咳嗽音量高低取决于呼出的空气量以及声带是否因为感染而肿胀，故选C。