补全句子。

1. _____ I listen to English I always listen to find _____ words.

2. When I read a text _____ the first time I often read it _____ to find the _____ _____.

3. When I look           a word           the dictionary, I often read the Chinese and English _____ and

    examples.

4. Many students ask me _____ they can _____ their progress.

5. A self-assessment is often           the form           questions, _____ example, what you have learned

    _____ this unit, etc.

6. _____ answering these questions, you can find _____ what and how you have learned.

7. A self-assessment doesn't have to _____ long.

导致锅炉爆炸的主要原因之一是（）

A.24小时不停地使用锅炉

B.炉水长期处理不当

C.炉渣过多