Question

________ in the queue for half an hour, Tom suddenly realized that he had left his wallet at home．

[　　]

A．

To wait

B．

Have waited

C．

Having waited

D．

To have waited

Answer 1

答案：C
解析：

B项是谓语动词形式，不可作状语，排除B项。A、D两项为不定式形式放在句首时常作目的状语，这显然与本题逻辑上不符。