问题 选择题

生活在沙漠里的仙人掌,叶变成刺而根、茎肥大,具有贮存水的作用,这一结构特点的形成是(  )

A.这些器官经常使用

B.为了能吸到更多的水

C.自然选择的结果

D.定向变异的结果

答案

达尔文认为,生物的繁殖过度引起生存斗争,生存斗争包括生物与无机环境之间的斗争,生物种内的斗争,如为食物、配偶和栖息地等的斗争,以及生物种间的斗争;在生存斗争中,具有有利变异的个体,容易在生存斗争中获胜而生存下去,反之,具有不利变异的个体,则容易在生存斗争中失败而死亡;生活在沙漠里的仙人掌,叶变成刺而根、茎肥大,具有贮存水的作用,是干旱环境对仙人掌进行长期的选择的结果.

故选C.

完形填空

第Ⅱ卷(共45分)

第四部分:书面表达(共两节,满分45分)

第一节阅读表达(共5小题;每小题3分,满分15分)

阅读下面的短文,并根据短文后的要求答题(请注意问题后的字数要求)

[1]Tere is always a way to be friends with everyone.Don't be afraid to talk to people.meetitrangers is the best way to make new friends!

[2]If the group you want to be friends with is a shy group,  and you' re a little more sciable, never ask them "Why don't you talk?" or "Why are you quiet?" They hate that. It'srude. Don't do it.If you' re shy and you want to get into a sociable gToup, then just try to get a little attention, but try not to overdoit.No one likes a show -off. And remember that each group will be different. Observe what is appropriate for each group, and act accordingly, but don't change yourself just to fit in.

[3] Always be outgoing, and going out.Be outgoing, and you will                     within a group.Go out a lot so that you will hang out wkh different groups. Being friends with everyone is time and energy consuming, because you must be friendly, outgoing, and willing to hang out, leaving very little time to yourself.That is something you have to consider before go- ing and trying to be so popular.

[4] However, being friends with everyone can be difficult.You may feel tom between  friends ;  who to hang out with ifit can' t be done at once. And if for any.reason you cannot con- tinue with the demanding time schedule, friends will fade rapidly. Make sure to have a couple strong friends, or it may be possible for all of your friends to become just acquaintances.

[5] Just remember: Don't forget who your real friends are. Don' t become friends with  someone just because they are a cheerleader or reaily popular.

76.What' s the best title of this passage? ( Please answer within 10 words)

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77.Which sentence( s)  in this passage could be replaced by the following one? .

Though you should make some mecessary changes in making friends, you still stick to who you are.

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78.Fill in the blank in the third paragraph with proper words to complete the sentence.( Please  answer within 5 words)

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79.What' s your advice about making fnends with others? Why? ( Please answer within 30 words )

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80.Translate the underlined sentence in the fourth paragraph into Chinese.

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单项选择题