问题 填空题

有A、B、C、D四种物质,已知A是无色无味的气体,B在A中燃烧更旺,生成无色气体C,C能使澄清石灰水变浑浊;D是空气的成分之一,约占空气体积的4/5,将红热B放入C或D中立即熄灭,又知C和D是不同物质,请写出A、B、C、D的化学式A是______,B是______,C是______,D是______.

答案

A是无色无味的气体,B在A中燃烧更旺,所以A为氧气;C能使澄清石灰水变浑浊,所以C为二氧化碳;D是空气的成分之一,约占空气体积的4/5,所以D是氮气;将红热B放入C或D中立即熄灭,B在A中燃烧更旺,生成无色气体C,所以B是碳.

故答案为:O2;C;CO2;N2

解答题
阅读理解

阅读理解。

     As we all know,sleep is very important and necessary.I would love everyone to form the habits

below to have better sleep.

     Eat right meals and don't have meals within 4 hours of rest.If you eat much food an hour before

you go to bed,your body will hate you.Your body needs time to digest (消化) while you are still

awake.

     Exercise for at least________every day.Sometimes I become very angry when I hear on TV that

people just need 30minute exercise a week.That's funny.Every person should be getting 30minute

exercise daily along with a healthy diet.When you do exercises,you use energy that your body has

to recover from.Your body recovers when you are sleeping.The_more_exercises_you_do,the_faster

_you_will_fall_to_sleep.

     Turn the TV off.There are a few shows I watch still,but they will never get in my way of (妨碍)

sleep.The bedroom is only for sleeping and it is a place for rest.You'd better take the TV out of your

bedroom.

     Throw away the alarm.You should ask yourself a question: If I didn't have an alarm,at what time

would I get up? If that time is the time you need to get up,you should probably throw away the alarm.

If the time you actually get up at is much later than the time you do get up at,make great changes to

your way of life and the time when you go to sleep.No one should need an alarm.

1.What would be the best title of the passage?  (Please answer within 10 words.)

________________________________________________________________________

2.Which sentence in the passage is the closest in meaning to the following one?

It is a better way for you to put the television outside your bedroom.

________________________________________________________________________

3.Fill in the blank in Paragraph 3 with proper words.(Please answer within 5 words.)

________________________________________________________________________

4.Why will your body hate you if you eat much food an hour before you go to bed? (Please answer

within 15 words.)

________________________________________________________________________

5.Please translate the underlined part in Paragraph 3 into Chinese.

________________________________________________________________________