提醒：点这里加小编微信（领取免费资料、获取最新资讯、解决考教师一切疑问！）
【动词的时态(六)】
现在完成时(二) 过去完成时
1.现在完成时难点：
① 由since引导的时间状语，它们的主句通常使用完成时态。
He has taught English since 1970.
It has been a long time since I last saw you.
② 只有在It is …since…这种结构中，主句的谓语才可用一般现在时，现在完成时或一般过去时。如：
It’s ten years since I left school.
It’s a long time since I saw you last.
③ 表示短暂性的动词不能与表示一段时间的状语连用，这类动词有：
begin, borrow, buy, close, come, die, fall, find, finish,
join, kill, lend, leave, sell, start, stop等，如：
不能说：His father has died for three years.
只能说：His father died three years ago.
不能说：He has left home for two months.
只能说：He left home two months ago.
④ 非延续性动词的否定形式可以表示状态的延续。可与for, since时间状语连用。如：
I haven’t seen him for a long time.
I haven’t heard from him since he left.
She hasn’t left home ever since she lost her job.
⑤ have(has) been 和have (has) gone的区别。
Have been to a place意思是“到过、去过”，表示曾到过某处，但现在人不在那儿;have gone to意思是“去了”，表示已经去了某地，现在人可能在去的途中或已在那儿。如：
Has she ever been to Nanjing?
You have never been there before, have you?
I have been to Guilin, I went there last year.提醒：点这里加小编微信（领取免费资料、获取最新资讯、解决考教师一切疑问！）
