現(xiàn)在完成時
1.基本用法
(1)在過去不確定時間里發(fā)生的并與現(xiàn)在有著某種聯(lián)系的動作，體現(xiàn)的是影響或結果。
（2）動作開始于過去并持續(xù)到現(xiàn)在的動作。（現(xiàn)在完成進行時）。
2.基本結構
主+have(has)+動詞的過分
注意其肯定、否定、疑問變化，動詞的過去分詞變化規(guī)律（略）。
3.現(xiàn)在完成時的時間狀語
Already,yet,just,recently,so far,for,since,up to now,in the past 2 years.
I’ve worked in the company for 2 years.
(1)如果完成時句子中后跟(for+一般時間）時，其謂語動詞須是持續(xù)性動詞;但如若后面未跟一段時間則可以用短暫性動詞；如果完成句是否定句且謂語是短暫性動詞，則后可跟一段時間。
They’ve come to visit us from time to time.
(2)相關動詞的相應轉換
borrow→keep(have)
come back→be back
He died 5 years ago.
He has been dead for 5 years.
He left his hometown many years ago
He has been away for many years.
4.相關難點
（1）have gone(to)have been(to)
(2)完成時與since(從句)
一般since從句中用的都是短暫性動詞的過去時。
He has been ill since I saw him last.
(3)如若since從句中用的是持續(xù)性動詞（靜態(tài)動詞）的過去時，則含義不同，其表示從句動作的完成或結束。
The house has been in bad repair since he lived in it.
The house has been in bad repair since he moved out.
I haven’t eaten snails since I was a student at Indiana University.
I haven’t eaten snails since I left Indiana University.
(4)如若since從句中的動作或狀態(tài)延續(xù)到說話時間，通常要用持續(xù)性動詞或表狀態(tài)動詞的現(xiàn)在完成時。
He has written to me frequenthy since I was ill.
自從病愈以來……
He has written to me frequenthy since I have been ill.
自從我生病以來……
I haven’t seen you since I’ve been back.
I haven’t seen you since I was back.
(5)區(qū)別
The house has been in bad repair since he lived in it.
The house has been in bad repair since he has lived in it.
He has stayed here for 3 hours.
He stayed here (since) 3 hours ago.
He has stayed here since 3 O’clock.
(6)在表示“第……次做某事”時常使用現(xiàn)在完成時。
It’s the 1st good meal I’ve had for ages.
It’s the 3rd time this has happened.
It’ll be the 1st time I’ve spoken in public.
(7)如果It之后的be動詞用的是was,則that分句中通常用過去完成時。
It was the 1st time he hadn’t worked on Saturday.
It was the 1st time she’d been at a summer school and she thoroughly enjoyed it.
1.基本用法
(1)在過去不確定時間里發(fā)生的并與現(xiàn)在有著某種聯(lián)系的動作，體現(xiàn)的是影響或結果。
（2）動作開始于過去并持續(xù)到現(xiàn)在的動作。（現(xiàn)在完成進行時）。
2.基本結構
主+have(has)+動詞的過分
注意其肯定、否定、疑問變化，動詞的過去分詞變化規(guī)律（略）。
3.現(xiàn)在完成時的時間狀語
Already,yet,just,recently,so far,for,since,up to now,in the past 2 years.
I’ve worked in the company for 2 years.
(1)如果完成時句子中后跟(for+一般時間）時，其謂語動詞須是持續(xù)性動詞;但如若后面未跟一段時間則可以用短暫性動詞；如果完成句是否定句且謂語是短暫性動詞，則后可跟一段時間。
They’ve come to visit us from time to time.
(2)相關動詞的相應轉換
borrow→keep(have)
come back→be back
He died 5 years ago.
He has been dead for 5 years.
He left his hometown many years ago
He has been away for many years.
4.相關難點
（1）have gone(to)have been(to)
(2)完成時與since(從句)
一般since從句中用的都是短暫性動詞的過去時。
He has been ill since I saw him last.
(3)如若since從句中用的是持續(xù)性動詞（靜態(tài)動詞）的過去時，則含義不同，其表示從句動作的完成或結束。
The house has been in bad repair since he lived in it.
The house has been in bad repair since he moved out.
I haven’t eaten snails since I was a student at Indiana University.
I haven’t eaten snails since I left Indiana University.
(4)如若since從句中的動作或狀態(tài)延續(xù)到說話時間，通常要用持續(xù)性動詞或表狀態(tài)動詞的現(xiàn)在完成時。
He has written to me frequenthy since I was ill.
自從病愈以來……
He has written to me frequenthy since I have been ill.
自從我生病以來……
I haven’t seen you since I’ve been back.
I haven’t seen you since I was back.
(5)區(qū)別
The house has been in bad repair since he lived in it.
The house has been in bad repair since he has lived in it.
He has stayed here for 3 hours.
He stayed here (since) 3 hours ago.
He has stayed here since 3 O’clock.
(6)在表示“第……次做某事”時常使用現(xiàn)在完成時。
It’s the 1st good meal I’ve had for ages.
It’s the 3rd time this has happened.
It’ll be the 1st time I’ve spoken in public.
(7)如果It之后的be動詞用的是was,則that分句中通常用過去完成時。
It was the 1st time he hadn’t worked on Saturday.
It was the 1st time she’d been at a summer school and she thoroughly enjoyed it.