Question

Since在现在完成时的用法?谢谢

Answer 1

since的意思是“自从”，它后面接时间点，它包含以下三种情况：

1、since＋过去时间

I have lived here since 2008.我自从2008年就住在这儿。（2008年是过去的时间）

2、since＋时间段＋ago

He has been away from here since three years ago.他自从三年前就离开这儿了。（three years为时间段）

3、since＋一般过去时态的句子

He hasn’t left here since he moved here.他自从搬到这儿，就没有离开过这儿。（he moved here是一般过去时态的句子）

其他用法

adv. （副词）

since用作副词表示“以前”时还可和long，ever连用。

long since意为“好久以前”，not long since意为“就在不久前”，ever since意为“从那时起,此后一直”。

Answer 2

现在完成时态中since的用法
1) since+过去一个时间点 (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.
3) since +从句
Great changes have taken place since you left.
Considerable time has elapsed since we have been here.
4) It is +一段时间+ since从句
It is two years since I became a postgraduate student.

Answer 3

(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。