内容正文:
现在完成时
定义:现在完成时表示过去发生或已经完成的某一动作对现在造成的影响或结果。
一、基本结构
谓语动词:have/has + done
其中have/has为助动词,done为动词过去分词;
肯定:They have finished their task.
否定:They haven’t finished their task.
疑问形式:Have/Has + 主语 + done + 其他?
Have they finished their task?
回答用Yes, …have(has)./ No, …haven’t(hasn’t).
二、过去分词
动词过去分词的构成分规则变化和不规则变化两种形式;
规则变化则同动词过去式的规则变化一样:
变化规则
举例
(1) 一般在动词后加-ed
play—played—played
want—wanted—wanted
(2) 以不发音的e结尾的加 -d
like—liked—liked
live—lived—lived
(3) 以辅音字母 +y结尾,变y为i再加 -ed
carry—carried—carried
hurry—hurried—hurried
(4) 以一个辅音字母结尾的重读闭音节词,双写字尾加 -ed
plan—planned—planned
stop—stopped—stopped
其不规则变化参照《动词不规则变化表》。
be-was/were-been go-went-gone
三、现在完成时应用
1. 表示过去发生或已经完成的动作对现在造成的影响或结果,其汉译常带有“完了,过了,已经”等意,
I have spent all of my money.
My father has gone to work.
2.现在完成时可以用来表示发生在过去某一时刻的、持续到现在的动作(用行为动词表示)或状态(be动词表 示),常与for(+ 时间段),since(+ 过去的时间点或过去时的句子)连用,谓语动词必须是延续性动词。如:
He has lived here since 1978. 自从1978年以来,他一直住在这儿。
They have leanrt Chinese in this school for 3 years. 他们在这个学校学汉语3年了。
【注意】1. since用法
作为介词,自从...以来,后面加时间点,与现在完成时连用。
He has been here since three years ago.
作为连词,自从...以来,主句用现在完成时,从句用一般过去时。
I have taught English in China since I came here.
It is/has been+时间段+since从句(一般过去时)
It is three years since I left Australia.
2.for 和since用法区分
for+时间段,累计的时间,一直进行多长时间。
since+时间点,某件事开始的时间。
They have been married for ten years.
They have been married since ten years ago
【练习1】用for和since填空
1. ________ two years2. ________ two years ago3. ________ last month
4. ________ 19995. ________ yesterday6. ________ 4 o’clock
7. ________ 4 hours8. ________an hour ago9. ________ we were children
10. ________ lunch time11. ________ she left here
现在完成进行时所用的时间状语:recently /; in the past few + 时间段; since +时间点; for + 时间段, so far,already 等等。如:
They have been building the bridge for two month. 两个月来他们一直在修桥。
We haven’t got any reply from her so far. 我们迄今为止还没有收到她的回复。
【练习2】1.I ____________ five books since I joined the book club.
A.am readingB.will readC.have read
2.—Do