When the sick mother got up she was surprised to find that her six-year-old daughter in

问题补充：

When the sick mother got up, she was surprised to find that her six-year-old daughter in the kitchen.

A. had cooked

B. has cooked

C. was cooking

D. cooked

答案：

A. had cooked

B. has cooked

(答案→)C. was cooking

D. cooked

解析：句意：当生病的妈妈起来的时候，她很惊讶的发现她六岁的女儿正在厨房做饭。Cook这个动作是发生在：When the sick mother got up,所以用过去进行时，选C。