句中时间状语前为什么用介词forHe then asked when Mr Gilbert would be allowed to go home and the doctor told him that he would have to stay in hospital for another two weeks.
问题描述：
句中时间状语前为什么用介词for
He then asked when Mr Gilbert would be allowed to go home and the doctor told him that he would have to stay in hospital for another two weeks.
答
for+时间段，表示持续一段时间。这句话的意思是：然后他问医生Gilbert先生什么时候可以出院回家，医生告诉他Gilbert先生还必须在医院再呆两星期.
答
用for表示这个时间段,时间上通常用介词for,本句就是：他得再多呆在医院两周,而不用for,则表示具体的时间点