“I bought this shirt for 35 Yuan yesterday.” “It’s on sale today for only 29.You should have waited.

题目

“I bought this shirt for 35 Yuan yesterday.” “It’s on sale today for only 29.You should have waited.” “Oh,really?But how ______ I know?
A.would B.can C.did D.do

答案

C 是过去式.使用过去式的时候,那个action必须发生在过去并且已经结束：＂How did I know?＂=＂我怎么知道的?＂说明那个Subject已经知道了.A是条件式.条件是通常是一种懊悔／感叹,意思就是没有发生,因为一些条件不具...