求since的用法归纳
since语法？
since语法？
since用法：翻译自从…以来”：
时间点，要求:v.使用现在完成，并且必须是连续动词；
接一段时间 ago，要求：谓v.当它现在完成时，它必须是连续性动词.。
(1) since 过去的时间点 例如具体的年、月、日期、钟点、1980 last month, half past six)。
I have been here since 1989.
(2) since 一段时间 ago
I have been here since five months ago.
since语法？
since用法：翻译自从…以来”
(1)连接时间点: I have stayed in that country since 1995. 要求：谓v.使用现在完成，并且必须是连续性动词。
(2)连一段时间 ago：如 They have lived in that house since two years ago. 要求：谓v.使用现在完成，并且必须是连续性动词。
(3)时间状语从句: I have loved her since I met her last time. / Lily has stayed at home since she left school. 要求：主句的谓谓v.当它现在完成时，它必须是一个连续的动词；从句的谓v.一般过去时，而且必须是终止性动词。
(4)用于句型It’s / It has been 一段时间 since 时间状语从句…以来, 已经…(时间)。如 It’s / has been three months since he moved to this city. 要求：主句的谓谓v.使用一般当前时间或当前完成时间；从句的谓v.使用一般过去时，是终止动词。
(5)用于一段时间的句型 has passed since 时间状语从句…以来, …
(时间)已经过去了。如前一个例句也可以写成：Three months has passed since he moved to this city. 要求：主句的谓谓v.当现在完成时，动词必须是has passed；从句的谓v.使用一般过去时，是终止动词。
(6)注：当since当用于否定句时v.可以是终止性动词。 He hasn’t seen the film since last month.
(7)相关短语:从那时起ever since、since then、from then on.
注：ever since作为一个短语，句尾可以单独使用。如I have given up smoking ever since. 另外，还可以since后接句子。since前加ever，只是加重了语气。如 I have given up smoking ever since I caught a bad cough.
(8) since它还可以引导原因状语从句，翻译为因为；因为because。如 Since he was lazy, he didn’t finish his homework.