内容正文:
第五讲 8B 现在完成时
一、知识梳理
现在完成时的定义
基本结构是助动词have/has+done、haven’t/hasn’t done
1.强调过去的动作对现在造成的影响。常被just、already、yet 等副词修饰。例如:
—Have you had lunch yet? 你已经吃午饭了吗?
—Yes, I have. I’ve just had it. 是的,吃过了。我刚刚吃过。(现在我不饿了)
—I have just cut my hair.我刚刚剪完头发。
—Wow,no wonder you look cool.哇,难怪你看起来这么酷。(我现在看起来更酷了)
2.表示从过去某一时刻开始一直持续到现在的动作或状态。这个动作可能刚停止,可能仍然在进行。常带有for和since等表示一段时间的状语。也常常与so far,in the past several/few years这类表示从过去到现在的时间状语连用。
—How long have you lived here?你住在这里多久了?
—I have lived here for about 10 years.我在这生活了十年了。
He has taught here since 1981. 他自1981年就在这儿教书。(可能还要继续教)
I haven’t seen her for four years. 我有四年没见到她了。
3.含有持续长度的时间状语的现在完成时的句子,不可用短暂性动词,只可用延续性动词或短语。
My dog has died for five years.(×) My dog has been dead for five years.(√)
常见的短暂性动词到延续性动词或短语如下:
短暂性动词
延续性动词或短语
borrow
buy
catch(a cold)
arrive
begin/start
leave
join
fail ill
die
open
finish
close
过去分词的规则变化以及不规则变化
1.规则变化:与动词过去式规则变化一致
①一般直接在词尾加上ed。如look — looked
②以e结尾的动词,直接加d。如move — moved
③以y结尾,y前面是辅音字母的动词,变y 为i,再加ed。如carry — carried
④部分动词需双写尾字母,加ed。如stop — stopped
2.不规则变化(常用):
原型
过去式
过去分词
AAA
cost
cut
hit
Let
put
ABB
understand
bring
build
burn
think
teach
ABC
be
begin
blow
break
do
go
ABA
become
come
run
常和完成时连用的时间状语
already, just, yet, ever, never, recently, since, for, so far, during/in/over the past few years…
辨析一般过去时和现在完成时
一般过去时表示过去发生的事,与现在没有直接关系,不强调对现在的影响,通常与一般过去时连用的时间状语,如:
1.yesterday或以其构成的短语:yesterday morning(afternoon, evening)等;
2.由“last+一时间名词”构成的短语:last night, last year (winter, month, week)等;
3.由“时间段+ago”构成的短语:a moment ago, a short time ago, an hour ago等;
4.其它:just now等
区分have/has gone to、have/has been to、have/has been in
1.have/has gone to:表示去了某地未归。
—Where is lily? —She has gone to the supermarket.You can wait for a while.
2.have/has been to:表示去过某地已回,可以是去过很多次。
—You seem to know a lot about China. —Sure,I have been (to) there twice.
3.have/has been in:表示在某地持续了一段时间,常