because 引导的原因状语从句是否要考虑与主句的先后关系而确定时态?（认真阅读说明）我们学校里老师说原因状语从句是无需考虑与主句的关系的（是什么时候发生就用什么时态）,但后来学了现在完成时中,包括百度百科里的介绍,很多题目等,都阐明了：原因状语从句中即便是过去发生的,却要用过去完成时比如：She came to the classroom because she had left book here.又如：The farmers were happy because they had got a big harvest（注明：这两句都是我在网上和语法书上看到的,绝对真实）但是,在做题时,又遇到了很多虽然从句中虽然从句中的动词发生在主语动词之前,却要用一般过去式的状况：如：SHE WOKE UP IN THE MID NIGHT BECAUSE SHE HAD A BAD DREAM(这里没用“had had”）HE DIDN'T COME TO SCHOOL BECAUSE HE HAD A
问题描述：
because 引导的原因状语从句是否要考虑与主句的先后关系而确定时态?（认真阅读说明）
我们学校里老师说原因状语从句是无需考虑与主句的关系的（是什么时候发生就用什么时态）,但后来学了现在完成时中,包括百度百科里的介绍,很多题目等,都阐明了：原因状语从句中即便是过去发生的,却要用过去完成时比如：
She came to the classroom because she had left book here.
又如：
The farmers were happy because they had got a big harvest
（注明：这两句都是我在网上和语法书上看到的,绝对真实）
但是,在做题时,又遇到了很多虽然从句中虽然从句中的动词发生在主语动词之前,却要用一般过去式的状况：如：
SHE WOKE UP IN THE MID NIGHT BECAUSE SHE HAD A BAD DREAM(这里没用“had had”）
HE DIDN'T COME TO SCHOOL BECAUSE HE HAD A CARACCIDENT.
这种情况怎么解释?
答
两种时态都可以用的.because引导的原因状语从句,当主句是一般过去时时,从句用一般过去时还是过去完成时,要看具体情况而非千篇一律用某种时态的.楼主的两个句子：She came to the classroom because she had left boo...