问题 填空题
根据句意和首字母及汉语提示完成单词。   
1. The s             on the teacher's face showed that she was pleased with us.
2.  Listen!There is somebody k           at the door.
3. There are n           34 million people living here.
4. Now stop writing and listen to me c            .
5. Trees and flowers are planted every year to make our country more b           
6. Pollution is a             (严重的) problem. Scientists have come up with some good ways to solve it.
7. It is            (必要) to learn English well.
8. A lot of meetings were put off because of the             (危险的) disease.
9. I           (不知道) if the teacher will come tomorrow.
10. Ann has made great             (进步) recently.
 
答案

1. smile    2. knocking    3. nearly    4. carefully    5. beautiful    6. serious

7. necessary    8. dangerous    9. wonder   10. progress

问答题
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