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since的用法

更新时间: 2021-05-22 14:22:05

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、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.

标签:since用法