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问题 单项选择题 A1型题

某年冬季，某地区居民因食用被甲肝病毒污染的毛蚶而发生甲型肝炎流行，此毛蚶称为（）

A.传染源

B.储存宿主

C.传播因素

D.传播机制

E.病原携带者

答案

参考答案：C

解析：

在外环境中参与传播病原体的因素称为传播因素，主要有空气、水、食物、土壤、用品和节肢动物等。

改错题

认真修改病句。     

1．我家屋后清澈地有一条小河。    

                                                                                               

2．这幅画的颜色全部涂完了，只剩一块山石没涂。

                                                                                              

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听力题

根据短文内容及首字母提示，填写所缺单词。(每小题1分，计10分)

Kitty was a student in a small town. It was going to be her mother’s birthday. She wanted to buy her a present that would be nice and useful but not e   1 .

She went s   2 after a quick and simple lunch. After she looked for about forty minutes, she found a shop that was selling cheap umbrellas, and she d  3 to take a black one. She thought, “Mom can carry it when she is wearing clothes of any c  4  .” So she bought a lovely black umbrella and took it to school with her until her classes finished.

On her way home on the train she felt h    5 . So she went to the buffet car (餐车). She left the umbrella on her seat. But when she r   6 , it had gone. Kitty began to cry. The other passengers felt very sorry for her and asked what the matter was. She told them the black umbrella she bought for her mother had gone, and she had to get off at the next station. After the three passengers h   7 this, they asked her for her mother’s a   8 so that they could send the umbrella to her if someone took it by mistake (弄错) and brought it b   9  .

And now a week passed. Kitty got a letter from her mother. It said, “Thank you very much for your lovely g   10  , but why do you send me three black umbrellas?”
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