1、since引导时间状语从句时，从句动词通常用一般过去时，主句动词用现在完成时。since引导原因状语从句对时态没有特殊要求。Since作为介词，后接某一确定的时间点，主句谓语动词是持续性动词，常与现在完成时态、现在完成进行时态或过去完成时态连用。
2、since后通常接一般过去时。当since表示自从时，不管它是用作介词、连词还是副词，它通常都要与现在完成时连用。当主句表示“多长时间”时，动词可用一般现在时，当主句谓语动词为seem等连系动词时是It seems like years since we last met。
3、since从句用延续性动词的现在完成时，则表示该动作或状态一直延续到现在时刻，而且可以包括现在时刻在内，时间的起点应从动作发生之时算起，句子的意思和动词的词意一致，具有肯定意味。
短语搭配
Since many.出自多；来自多；外射门自多
Ever since.自从；正在翻译；从那以后
Since childhood.自幼；自小；自小时候
since both.因为这两种；因为两者
Collaboration since.自协作；自从协作；协作自
Since Technology.圣驰科技
president since.自总统；总统以来
Sculpture Since.西方当代雕塑
双语例句
1、You've grown since the last time I saw you!
自从我上次见到你后，你又见长了！
2、She's a changed woman since she got that job.
她自从得到了那份工作，变得判若两人。
3、She's been using since she was 13.
她从13岁起就吸毒。
4、His quality of life has improved dramatically since the operation.
手术后他的生活质量大大改善了。
5、It's a long time since they left.
他们已经离开很久了。
6、It's been two weeks now since she called.
她到现在已经有两个星期没来电话了。
7、I had been out since I was 17.
我从17岁起就公开我是同性恋。
8、The children are completely out of control since their father left.
这些孩子自他们的父亲离开后就无法无天了。
9、It's been an age since we've seen them.
我们有很长一段时间没有见到他们了。
10、Since he changed jobs he's looked like a new man.
他跳槽之后像换了一个人似的。
11、I haven't seen him since the summer before last.
我已有两个夏天没见过他了。
12、They've been best friends since they were children.
他们从孩提时起就是最要好的朋友。
13、He's been working in a bank since leaving school.
他中学毕业以后一直在一家银行工作。
14、He had been with the company since its creation in 1989.
他从1989年公司成立以来，就一直在那里工作。
15、It's exactly a year since I started working here.
我来这里工作已经整整一年了。
