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问题 单项选择题 A1/A2型题

样品的醇溶液+NaBH+浓HCl生成紫-紫红色，则可能含有（）

A.黄酮

B.黄酮醇

C.二氢黄酮类

D.异黄酮类

E.查耳酮

答案

参考答案：C

解析：NaBH是对二氢黄酮类专属性较高的还原剂，与其反应可见红至紫色，所以答案为C。

连词成句

仿照例句用所给的词汇造句。

例：I, do my homework, last night

       I was doing my homework last night.

A. they, have a dress rehearsal, yesterday evening

                                                                              

B. my grandma, visit my family, half an hour ago

                                                                              

C. I, travel in the south, at this time last year

                                                                              

D. they, build a power station, at that time

                                                                              

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填空题

根据句意和首字母填空。

1.  B______ a drum (鼓) makes me happy.

2.  Class 7 ______ Class 6, we ______  them. As you can see, we ______  the match,

     we were winners.

3.  My father is very busy, he doesn't c______ what I do.

4.  Don't smoking. Take c______ of your health, please.

5.  You should do everything c______, you can't be a c______  boy.

6.  I'm very happy, because I have f______  of forty years with them.

7.  He is more than six, so it is time for him to go to the p______ school.

8.  There ______  some useful i______  on the Internet.
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