问题描述：
he fled,slamming the door behind him 为什么有两个时态
When Mrs.Richards walked towards him,he fled,slamming the door behind him,这里fled为过去式,slamming为进行时,为什么出现两种时态
When Mrs.Richards walked towards him,he fled,slamming the door behind him,这里fled为过去式,slamming为进行时,为什么出现两种时态
问题解答：
我来补答展开全文阅读