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问题 选择题

蕨类植物一般生长在（　　）

A．在阴湿的地面或背阴的墙壁上

B．在森林和山野的阴湿环境中

C．生长在淡水或海水中

D．生活在各种环境中

答案

蕨类植物不结种子，靠孢子繁殖后代，当孢子萌发时可形成原叶体．原叶体的腹面上长有雌、雄生殖器官，当原叶体被水浸湿时，精子游到雌性生殖器官里与卵细胞结合完成受精作用，形成受精卵，由受精卵再发育成新的植物体．可见蕨类植物的受精作用离不开水，同时蕨类植物有了根、茎、叶的分化，体内有输导组织为植株输送大量的营养物质供植株生长利用，还有机械组织支持地上部分，一般长的比较高大，因此蕨类植物不适合生活在水中或背阴的墙壁上，一般生活在森林和山野的阴湿环境中．

故选：B

单项选择题

In the United States and in many other countries around the world, there are four main ways for people to be (91) about developments in the news: newspapers, magazines, and radio or television news broadcasts. A person may use one, or all, of these (92) for information. Each source is useful in its (93) way. Newspapers and magazines can give much information about a particular event. They may (94) some history of the event, some of its (95) , some of its effects, or perhaps give an (96) or point of view on a particular development. Radio and television can help a person to be well informed about what is happening each day. It is also (97) to listen to radio or watch TV (98) do something else at the same time. Many people can listen to the news on their car radio while driving (99) . For the student of English as a foreign language, an English language newspaper may be the most helpful news source that will also (100) you practice in reading English.
Most daily English language newspapers are not very hard to find. They are interesting and helpful in many (101) . In some of them, you may be able to find news about your (102) country. You will find news and information about important national and international political (103) . (104) what you are interested in, you can probably find something in the newspaper about it. A(n) (105) in the newspaper may help you solve a problem. Other stories may be about good movies, concerts, or TV shows.
Usually, an English language newspaper has several (106) or parts. Each part of the newspaper (107) stories about different kinds of news. Some sections have a lot of advertisements which may be helpful if you want to save money. By reading the advertisements, you may find something you want (108) sale. Or you may find that two stories are advertising the (109) thing, but at one store the price is lower. Other sections may have (110) advertisements or have only a specific type of advertisement to interest the people.

A．sections

B．portions

C．divisions

D．chapters
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选择题

将浑浊的河水用右图所示的简易净水器进行净化，其中活性炭的作用是

A．沉淀

B．消毒

C．吸附

D．蒸馏
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