初中现在完成时讲解练习及答案_

现在完成时精讲和专练

I.定义：

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，也能够表示过去已经开始，一直延续到现在的动作或状态

II.

注意：表示短暂时间动作的词，如：come，go，die，marry，buy等的完成时不能与for，since等表示一段时间的词连用。用来持续的动作或状态或表过去重复的动作，如live，study，be，wait等，常和since（自从）或for（经历）引导的词语连用。

如：I have lived here for more than thirty years.我已在此住了30多年。

III.现在完成时的标志

1. 现在完成时的含义之一是过去完成的动作对现在仍有影响, 现在完成时通常和，ever, never, twice（once…）, so far（到当前为止）, since，for，in the past/last few years（在过去几年）, already（肯定句）, yet（否定，疑问句）, just(刚刚), before（以前）, recently （近来）等词连用

说明：already与yet都有“已经”的意思，但already常用于肯定句，并用于句中。yet 常用于否定句和疑问句，并用于句末。例如：

I have already finished my homework.

I haven’t finished my homework yet. Have you finished your homework yet?

They have left. (他们已经离开了,也就是说现在他们人不在这里)

I have had my lunch. (我已经吃过午饭了,也就是说我现在不饿)

I can’t find my watch now. I think I have already lost it.

2.过去已经开始的动作一直延续到现在, 甚至有可能继续延续下去,我们能够从动作“延续”的特性和“时间”点段的区分入手。

①for+时段②since+过去一个时间点（过去从句）为标志

注意：1)现在完成时不能单独与过去的时间状语连用, 如yesterday, last week, three years ago 等;

2)不能与when连用

IV.现在完成时的用法

A．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，强调对现在造成的影想或结果）。例如：

The car has arrived. 车子来了。（结果：车子已在门口）

Someone has broken the window.有人把窗户打破了。（结果：窗户仍破着）

B. 表示过去已经开始，持续到现在的动作或状态，能够和表示从过去某一时刻延续到现在（包括“现在”在内）的一段时间的状语连用,如for+时间段、since+过去的时间点、疑问词how long等。例如：

My uncle has worked at this factory for five years.

我叔叔在这个工厂工作已经五年了。

Mr. Black has lived in China since 2002.

自从2002年Mr. Black 一直住在中国。

How long have you been here?

注意：例如：(1)这本书我已经买了三个月了。

错误：I have bought the book for three months.

准确：I have had the book for three months.

(2)你哥哥参军多长时间了？

错误：How long has your brother joined the army?

准确：How long has your brother been in the army/been a soldier?

延续性动词与非延续性动词之间的转换

leave --- be away

borrow --- keep

buy --- have

die --- be dead

begin/start --- be on finish --- be over

fall ill ---be ill

get up---be up

catch a cold --- have a cold put on→ wear

come/become/go --- be here

fall asleep --- be asleep

get to/ arrive/reach --- be (in)

get to know --- know

join----be a member of ... (成为…的一员) open ---be open

close ---be closed

用相对应的延续性动词替换短暂性动词，句中谓语动词用现在完成时，时间状语为“for＋时间段”或“since ＋时间点”。如：

He has been in the Green China for three years.

He has been a member of the Green China for three years.

他加入“绿色中国”已经三年了。

The old man died 4 years ago.---- The old man has been dead for 4 years.

He joined the Party 2 years ago.---- He has been in the Party for 2 years.

I bought the book 5 days ago.---- I have had the book for 5 days.

表示时间段的短语有：

for+一段时间(for 2 years), since+从句(since he came here), since+时间点名词( since last year, since 5 days ago),how long; for a long time等。

V.现在完成时态与一般过去时态的区别

1一般过去时表示过去某时发生的动作或单纯叙述过去的事情，强调动作；现在完成时为过去发生的，强调过去的事情对现在的影响，强调的是影响。

I saw this film yesterday.（强调动作发生的时间是yesterday 。）

I have seen this film.（强调对现在的影响，电影的内容已经知道了。）

2一般过去时和表示过去的时间状语连用，如：…ago, last week/...

In 2008, in the past, just now, the day before yesterday, yesterday ...

Then(那时),that day, one day, once(从前)

现在完成时常和recently（近来），ever, never, twice, so far（到当前为止）, since，for，in the past/last few years , already（肯定句）, yet（否定，疑问句）, just(刚刚), before（以前）连用。现在完成时不与表示过去的时间状语连用。

现在完成时可表示持续到现在的动作或状态，动词一般是延续性的，如live, teach, learn, work, study, know.