英语现在完成时主要用法?现在完成时的用法、结构、标志词、动词变化要详细一点的、谢谢了、

英语现在完成时主要用法?现在完成时的用法、结构、标志词、动词变化要详细一点的、谢谢了、
英语现在完成时主要用法?
现在完成时的用法、结构、标志词、动词变化
要详细一点的、谢谢了、

英语现在完成时主要用法?现在完成时的用法、结构、标志词、动词变化要详细一点的、谢谢了、
have(has)+过去分词
1.现在完成时用来表示现在之前已发生活或完成的动作或状态,但其结果却和现在有联系,也就是说,动作或状态发生在过去但它的影响现在还存在.
I have lost my wallet.(含义是:现在我没有钱花了.)Jane has laid the table.(含义是:已可以吃饭了.)
2.现在完成时可以用来表示发生在过去某一时刻的,持续到现在的情况,常与for,since连用.
Mary has been ill for three days.I have lived here since 1998.
3.现在完成时往往同表示不确定的过去时间状语连用,如already,yet,just,before,recently,lately等:
He has already obtained a scholarship.I haven't seen much of him recently (lately).
4.现在完成时常常与表示频度的时间状语连用,如often,sometimes,ever,never,twice,on several occasion等:
Have you ever been to Beijing I have never heard Bunny say anything against her.
5.现在完成时还往往可以同包括现在时间在内的时间状语连用,如now,up to these few days/weeks/months/years,this morning/week/month/year,now,just,today,up to present,so far等:
Peter has written six papers so far.
6.现在完成时表示现在之前业已完成的动作,虽然其效果或影响仍然存在但已不再继续,但是有一些现在完成时的句子,在后面加上for+一段时间,则现在完成时的动作就表示延续性.
Thomas has studied Russian.(现在不再学俄语)
Thomas has studied Russian for three years.(=Thomas began to study Russian three years ago,and is still studying it now.(同第2点用法第一个例句)
7.现在完成时还可以用来表示过去的一个时间到现在这段时间内重复发生的动作.
We have had four texts this semester.
延续性动词是说动作本身可以延续一段时间,如 wait,eat,listen,write,learn等.非延续性动词则刚好相反,它是在瞬间或很短的时间内完成.这样的动词有：come,go,buy,leave等等.
代替终止性动词的方法 （2）
a)用延续性动词代替终止性动词
1、用have代替buy
My brother has had(不能用has bought) this bike for almost four years.
2、用keep或have代替borrow
I have kept(不能用have borrowed) the book for quite a few days.
3、用be替代become
How long has your sister been a teacher?
4、用have a cold代替catch a cold
Tom has had a cold since the day before yesterday.
5、用wear代替put on
b)用“be＋形容词”代终止性动词
1、be＋married代marry 2、be＋ill代fall (get) ill
3、be＋dead代die 4、be＋asleep代fall (get) asleep
5、be＋awake代wake/wake up 6、be＋gone代lose,die,sell,leave
7、be＋open代open 8、be closed代close/shut
9、be＋missing(gone,lost)代lose
c)用“be＋副词”代终止性动词
1“be＋on”代start,begin
2“be＋up”代get up
3“be＋back(to)”代return to,come back to,go back to
4“be here (there)”代come(arrive,reach,get) here或go (arrive,reach,get) there等等
d)用“be＋介词短语”代终止性动词
1.“be in/at +地点”代替go to /come to
2.用be in the army 代替join the army
3.“be in/at +地点”代替move to

have+动词的过去分词

现在完成时的公式：
主语+have（has）+动词的过去分词+宾语+表示时间的状语。

has加过去分词