Ⅰ．单词拼写（须用本单元的单词和词汇）
1. After graduation he took an o______________as a teacher in the city.
2. The a______________offered by the manager is difficult for him to finish.
3. An expert is a man who is engaged in p______________ business.
4. All his c______________who work with him in the same factory are all ready to help others.
5. You should c_____________on your work when you study.
6. In the__________（案子） of Ma Haitao， he was treated unfairly.
7. We also can a__________________knowledge during playing.
