动词的时态在英语学习中起着举足轻重的作用,也是AEAS考试语法部分的重点.今天A加未来小编带大家一起来针对某些特殊句式中的时态加以归纳分析，希望能够帮助大家更好的进行AEAS考试的学习和准备。
1.“主将从现”原则
即若主句为一般将来时，时间和条件状语从句通常要用一般现在时表示将来，而不能直接使用将来时态。如：
I’ll give her the telex when she comes.她来时把电传交给她。
I’ll return the book as soon as I have read it.这书一看完我就送还。
He’ll have four years at university after he leaves school.他中学毕业后要上四年大学。
2.since与完成时
since引导时间状语从句时，其主句通常要用现在完成时，有时也用现在完成进行时。如：
She has had another baby since I saw her last.从上次我见到她以来，她又生了一个孩子。
He has grown an inch since I saw him.我上次见到他以后他已长高了一英寸。
注：当主句为“It+be+一段时间”时，则通常用一般现在时代替现在完成时。如：
It’s more than three years now since I saw her last.我们已有三年多没见面了。
3.特定句式的时态
由no sooner...than,hardly[scarcely]…when引出的时间状语从句，其主句通常用过去完成时，从句通常用一般过去时。如：
Hardly had he arrived when she started complaining.他刚到她就抱怨起来。
No sooner had he gone to sleep than the telephone rang.他刚睡着电话铃就响了。
We had no sooner set out than a thunderstorm broke.我们刚出发就下起一阵雷暴。
No sooner had she agreed to marry him than she started to have terrible doubts.她刚同意嫁给他她就开始产生可怕的疑虑。