10. The scientists were waiting to see the problem 　　　　.　

A. settle　　 　　 B. settled　　 　 C. to settle　　 D. settling

9. The foreigner tried his best, but he still couldn't make his point 　　.

A. understand　 　　　　 B. understanding 　　　 C. to understand 　 　　 D. understood

8. People 　　　　in the city do not know the pleasure of country life.

A. live　　 　　　 B. to live　　 　 C. lived　　 　　 D. living

7. The 　　　　　price will save you one dollar for each dozen.

A. reduce　　 　 B. reducing　　 　　　 C. reduced　　 D. reduces

6. The student corrected his paper carefully, 　　　　the professor's suggestions.　

A. follow　 　　　 B. following　 　　 C. followed　 　　　 D. being followed

5. He went from door to door, 　　　　　waste papers and magazines.　

A. gathering　　　　　 B. gathered　 　　　 C. gather　　 　 D. being gathered

4. 　　　 　the office, the foreign visitors were shown round the teaching building. 　

A. Having shown　 B. Showing　 　 C. Has shown　 　　　 D. Having been shown

3. With winter 　　　　　on, it's time to buy warm clothes.　

A. came　　 　　 B. comes　　 　 C. come　　 　　 D. coming

2. Deeply 　　　　, I thanked her again and again.　

A. being moving　 B. moved　　 　 C. moving　　 D. to be moved

1. 　　　　 　how to do the homework, I went to ask my teacher for help.

A. Not to know　 　　 B. Not knowing 　　　　 C. Knowing not　 　　 D. Not known