since只能用在现在(过去)完成时中吗?

since只能用在现在(过去)完成时中吗?

是的

除了用于 现在完成时+since+过去时间 还可以用于 It is 一段时间+since+过去时间

since 还有因为的意思呢 做原因状语从句 所以不光是在完成时中

 不完全是 since的用法:译作“自从…以来” (1)接时间点:如 i have stayed in that country since 1995. 要求:谓v.用现在完成时，而且须是延续性动词。 (2)接一段时间 + ago:如 they have lived in that house since two years ago. 要求:谓v.用现在完成时，而且须是延续性动词。 (3)接时间状语从句:如 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v.用现在完成时，而且须是延续性动词;从句的谓v.用一般过去时，而且须是终止性动词。 (4)用于句型“it’s / it has been + 一段时间 + since + 时间状语从句”中，译作“自从…以来, 已经…(时间)了”。如 it’s / has been three months since he moved to this city. 要求:主句的谓v.用一般现在时或现在完成时;从句的谓v.用一般过去时，而且须是终止性动词。 (5)用于句型“一段时间 + has passed since + 时间状语从句”中，译作“自从…以来, … (时间)已经过去了”。如上个例句还可写成:three months has passed since he moved to this city. 要求:主句的谓v.用现在完成时，而且动词必须是has passed;从句的谓v.用一般过去时，而且须是终止性动词。 (6)注:当since用于否定句时，主句的谓v.可以是终止性动词。如 he hasn’t seen the film since last month. (7)相关词组:“从那时起”:ever since、since then、from then on. 注:ever since作为一个词组，放句尾可单独使用。如i have given up smoking ever since. 另外，还可在since后接句子。since前加ever，只是加重语气而已。如 i have given up smoking ever since i caught a bad cough. (8) since还可引导原因状语从句，译作“由于;因为”，相当于because。如 since he was lazy, he didn’t finish his homework.