题目内容：

doing的形式：doing,being done,having done,having been done有什么区别?
如果能举例的话,可以举几个例子么?

优质解答

doing 现在进行时I am answering your question 我正在回答你的问题being done,现在进行时的被动语态Your question is being anwered. 你的问题正在被回答having done,现在分词情况Having answered your question, I...