问题 选择题

下列物质含有氧分子的是

A.高锰酸钾

B.二氧化碳

C.二氧化锰

D.空气

答案

答案:D

题目分析:含有氧分子,即含有氧气。含有氧分子的物质,可能的氧气也可能是含有氧气的混合物。高锰酸钾中含有氧元素;二氧化碳中含有氧元素,一个二氧化碳分子中含有2个氧原子;二氧化锰中含有氧元素;空气是由氮气、氧气等气体组成的。故选D。

单项选择题
阅读理解

Some people have very good memory(记忆力) and they can easily remember quite long texts. There are other people who can only remember things when they have said them again and again. The famous English writer Charles Dickens said that he could walk down any long street in London and then tell you the name of every shop he had passed. Many great men of the world have a wonderful memory.

A good memory is greatly helpful in learning a language. Everybody learns his own language by remembering what he hears when he is a small child, and some children, like the boys and girls who live abroad(国外) with their parents, seem to learn two languages almost as easily as one. In school it is not so easy to learn a second language because the students have so little time for it, and they are very busy with other subjects too.

A man’s mind is like a camera, but it takes photos not only of what we see but also of what we feel, hear, smell and taste. When we take a real photo with a camera, Some people have very good memory(记忆力) and they can easily remember quite long texts.In the same way, there is much work to be done before we can keep a picture forever(永远) in our minds.

Memory is a diary, and we all carry it about us. We keep things we have experienced (经历)in this diary.

小题1:Which of the following is true?

A.Charles Dickens had a good memory because he was a famous writer.

B.People without a good memory cannot be great men of the world.

C.People became great because they have a good memory.

D.Many people may never become great though they have a good memory.小题2:To learn a language well, one must ________.

A.live abroad

B.write it every day

C.often hear it

D.go to school小题3:The writer thinks a camera in one’s mind can take photos of ______.

A.what we see

B.what we feel and hear

C.what we smell and taste

D.what we see, feel, hear, smell and taste小题4:If you have a good memory, ________.

A.you can learn a second language easily

B.you can remember things for ever easily

C.you can learn your own language easily

D.you can remember things better小题5:Which of the following is true?

A.We all keep a diary in our mind.

B.One has to do a lot of work before he can keep a picture in his mind forever.

C.A person with a good memory can remember things forever.

D.A good memory helps to remember everything forever.