____in the queue for half an hour,Tom suddenly realized that he had left his wallet at homea:To waitb:Have waitedc:Having waitedd:To have waited

问题描述:

____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

C
wait的行为也是由Tom做得,并且两个动作是同时发生的.所以用进行时态的分词.