Seeing the roadwith snow we had to spend the holiday at home watching TV.A. blocking B. to

问题补充：

Seeing the roadwith snow,we had to spend the holiday at home,watching TV.

A. blocking

B. to block

C. blocked

D. to be blocked

答案：

A. blocking

B. to block

(答案→)C. blocked

D. to be blocked

解析：过去分词表示被动。