题目内容：

英语only after the earthquake happened why a smelly gas came out of
only after the earthquake happened _______ why a smelly gas came out of the cracks in the well walls.
A.did people know B.have people known
B为什么不行?

优质解答

only+时间状语引起的倒装句用部分倒装,你的问题要看句子的时态,句子不倒装的话是：people_____(know){why a smelly gas came out of the cracks in the well walls }only after the earthquake happened.通过after这...