在表示一个具体的.个别的或将来的动作时,要用动词不定式.如: My job is to teach the first-year students grammar. To study English well is very important. 在表示比较抽象的一般的行为和动作时,二者可以互换.如: To climb mountains is a good form of exercise. Climbing mountains is a good form of exercise. 【查看更多】

 

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在某一精母细胞中,有一对染色体中一个单体的基因顺序为 1234 。 5678 ,另一个为 1265 。 4378 (中间的“。”表示着丝粒)。如果在减数分裂时在 3 和 4 之间发生了一次交换,在它所形成的四个配子中,这个染色体的构成分别是


  1. A.
    1234 。 56781256 。34218734 。5678 1265 。4321
  2. B.
    1234 。 56781256 。43788734 。5612 1256 。4321
  3. C.
    1234 。 56781265 。43218734 。5678 1265 。4378
  4. D.
    1234 。 56781265 。43211234 。5678 8765 。4387

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通读下面和短文,然后在后面所给的四个选英中,选出一个最佳答案.

 Bill and Fred were students at a university (大学) and they were friends. They didn't have    1  , so when it was time  2  their holidays, Bill said,“Let's take our holidays in a trailer (拖车), Fred. It's cheaper than a hotel. I can  3  my father's trailer. ”Fred was very happy, so they got into the trailer to begin their  4  .

 They wanted to get up  5  to go fishing, but they didn't have an alarm clock (闹钟).

 “That's all right, Bill,” Fred said. “I'll put these small pieces of bread  6  the top of the trailer tonight and they'll  7  in the morning.”

 Bill was very  8  , but he didn't say anything.

 Fred was right.  9  the day broke, small birds came down to eat the bread, and their    10  woke up Bill and Fred very quickly.

                                                                                                                                                     

1.A.any    money

B.much    money

C.little    money

D.many    money

[  ]

2.A.to

B.with

C.for

D.take

[  ]

3.A.lend

B.borrow

C.for

D.take

[  ]

4.A.holidays

B.work

C.practice

D.play

[  ]

5.A.the    next day early

B.early    the next day

C.late    the next day

D.the    next day late

[  ]

6.A.in

  

B.under

  

C.on

  

D.beside

  

[  ]

  

7.A.wake    up us

B.wake

C.wake    up

D.wake    us up

[  ]

8.A.happy

B.surprised

C.unhappy

D.nice

[  ]

9.A.Before

B.If

C.As soon as

D.Then

[  ]

10.A.sound

B.noise

C.singing

D.words

[  ]

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翻译句子。

1.没有足够的水生活会是什么样?这是难以想象的。

2.这是他们在亚洲要参观的第二个国家吗?

3. 机器人可以为你做家务,除非你喜欢自己做。

4. 为了使教室像新的一样,我们每天打扫。

5.我们不确定他们那时正在谈些什么。

 

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这故事发生在一月份一个寒冷的下午。

The story ________ ________ ________ ________ afternoon in January.

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父亲节(Fathers’ Day)是美国节日。 在每年6月的第二个星期日举行。 现在, 父亲节在我国也越来越流行。 父亲节来临, 你的同学都准备着为自己的爸爸准备礼物。 但你有自己的计划。 请根据以下的提示,用英语写一篇短文。

(1)、让爸爸休息一天。帮爸爸妈妈做一天的家务;

(2)、和他们聊天,谈生活中的事,听一听他们的建议。

(3)、为他们照一张相片。

要求:(1)内容完整;条理清楚,书写工整。

(2)前后连贯,符合英语的表达习惯,字数80字。

 

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