Here are the best choices for each blank:

1. While I **was washing** dishes last night, I **dropped** a plate.
(Answer: **C. was washing; dropped**)

2. This shirt is made of **man-made** fabric, but it feels like silk.
(Answer: **C. man-made**)

3. **Despite** his poor English, he managed to make himself understood.
(Answer: **C. Despite**)

4. When I returned home from work, I found that someone **had broken** into my house.
(Answer: **C. had broken**)

5. **The unemployed** always need help from the society and the government.
(Answer: **D. The unemployed**)

6. Don’t ever forget **to make** an appointment if you want to see the headmaster.
(Answer: **B. to make**)