since和before哪个前后时态一致?
网友回答
before 引导的状语从句,表示主句的动作发生在从句的动作之前;
We cleaned the classroom before we laft school.
He had been a cook before he went to college.
since 引导的状语从句,主句常用现在完成时,从句常用一般过去时;
We haven't seen each other since we parted.
======以下答案可供参考======
供参考答案1:
since和before两个前后时态都无法一致。
供参考答案2:
视情况而定，不能一概而论。一般来说、since前面更多出现完成时态后面出现过去时。