题干

在探究“馒头在口腔中的变化”时,进行了三种处理:

①将馒头碎屑与唾液放入1号试管中充分搅拌;

②将馒头碎屑与清水放入2号试管中充分搅拌;

③将馒头碎屑与唾液放入3号试管中不搅拌.

将这3支试管一起放到温水中,5~10分钟后取出,各滴加2滴碘液,摇匀.

请回答:

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同类题1

阅读下面的短文,将画线的句子译成英文或中文。

    Stephen Hawking was born in Oxford, England on 8th January, 1942. He went to school in St Allbans, a small city near London. ⑴尽管他做得很好,但是拿不到第一名。

    After leaving school, Hawking went first to Oxford University where he studied physics and then went to Cambridge University where he studied cosmology(宇宙学). As he himself admits, he didn't work hard. He was a very lazy student, and did very little work. However, he still got high marks.

   ⑵ 在他20岁的时候,他的身体出毛病了。 He started to knock into things. When he visited his family at Christmas time, his mother was so worried that she made him see a doctor. Hawking was sent to hospital for tests. Finally, the result came back. Hawking had motor neuron disease(运动神经元病). ⑶The illness would make him unable to speak, breathe or move without the help of a machine. Doctors said they had no way to help him. He would die before 23.

    At first, Hawking became very sad. After a while, though, he began to see his life in a different way. As he later wrote, “Before my illness was diagnosed(诊断), I had been very bored with life. There had not seemed to be anything worth doing. But shortly after I came out of hospital, ⑷I suddenly realized that there were a lot of valuable things I could do.” Then Hawking got married and found a job at Cambridge University as a professor. ⑸He strongly believes that his story shows that nobody should lose hope, no matter how bad their situation is. “Life is not fair.” He once said. “You just have to do the best you can in your own situation.”

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