since引导的时间状语从句主句用延续性还是瞬间性动词

问题描述:

since引导的时间状语从句主句用延续性还是瞬间性动词

这样看主句是表肯定还是否定:(可参考下面解析)1.若since引导的状语从句的谓语是终止性动词的过去时,则从句表示的时间是“从动作开始的那一时刻起”.例如:He has studied very hard since he came to our school...