Present Perfect
现在完成式
We use the present perfect tense to talkabout things that happened in the past which have a connection to the present.
我们用现在完成式表达在过去发生现在已经完成的事情。
Structure
句型
To make the present perfect tense, we use:
现在完成式的句型：
I/you/we/they + have + past participle
It/he/she + has + past participle
For most verbs, the past participle is thesame as the past simple:
大多数的动词过去完成式和过去式是一样的
例如：
lookedàlooked
playedàplayed
triedàtried
Examples: eat
以eat为例
Positive statement
肯定句
Ihave eaten breakfast already.
I’veeaten breakfast already.
Negative statement
否定句
Ihave not eaten breakfast yet.
Ihaven’t eaten breakfast yet.
Question
疑问句
Haveyou eaten breakfast yet?
Been or gone?
用been还是gone？
We use:
- been for visits which have been completed
been表示visit已经完成，过去曾经在某地现在不在
- gone for visits which have not been completed
gone表示visit未完成，过去曾经在某地现在还在
例如：
My friend visited Australia in 2006.
He has been to Australia.
He flew to Australia last week & isstill there.
He has gone to Australia.
We use the present perfect to talk aboutunfinished periods of time.
我们用现在完成式表示在某个的时间上尚未完成的事情
例如：
I haven’t seen my mother today.
(I didn’t see her today, but I still mightsee her before today is over)
I’ve eaten two sandwiches this week.
(I already ate two sandwiches and I mighteat some more before the week’s end)
We use the present perfect to talk aboutunfinished periods of time.
I haven’t seen my mother today.
(I didn’t see her today, but I still mightsee her before today is over)
I’ve eaten two sandwiches this week.
(I already ate two sandwiches and I mighteat some more before the week’s end)
We use the present perfect to talk aboutsomething that started in the past and continues into the present
我们用现在完成式表示某事从过去开始发生持续到现在。
例如：
I have lived here for three years.
(I started living here 3 years ago & Istill live here)
since or for
用since还是for
Since is used for a specific start time inthe past
since表示具体某个开始的时间点
例如：
(e.g. July, 2010, last Monday)
I have known hersinceJuly.
I have lived heresince2010.
For is used for a period of time
for用来表示具体的一段时间
(e.g. 3 years, a month, 5 minutes, an hour)
I have known herfora month.
I have lived herefortwo years.
今日作业：
完成Homework Sheet
