现在完成时难点解析

曲永华

一、for与since

当句中有“for +段时间”或“since +点时间”等时，主句常用现在完成时，谓语动词必须是延续性动词，若是非延续性动词，要改为延续性动词或表状态的词（短语）。

1. for +一段时间

I have been here for 2 weeks. 我到这里两周了。

He's studied English for 17 years. 他学习英语已经17年了。

2. since +表示过去某一时间的时间点

I have been here since 3 years ago. 三年前我就来这里了。

I have been here since I graduated in 1988. 从1988年毕业后我就来这里了。

【温馨提示】 since也可单独使用，表示“自那时起”;另外，since前也可加上ever，以加强语气。

It is nearly two years since I came here. 我来这儿快两年了。

I have been here （ever） since I graduated in 2015. 自从2015年毕业后我就来这儿了。

对for或since引导的时间状语提问必须用how long，不能用when。

—How long have you lived here？ 你住在这里多久了？

—I have lived here for 10 years. 我住在这里10年了。

二、短暫性动词与延续性动词详解

1. 短暂性动词：表示动作一开始马上就结束，不能延续，也叫非延续性动词或终止性动词。

常用的词有：begin 开始;close 关，关闭;finish 完成，结束;hear 听，听到，听说;lend借给;marry 结婚，嫁，娶;open 打开;put 放;receive 收到，接收;sell 卖，推销;start 开始，出发;stop 停止，终止等。

短暂性动词不能与表示一段时间的for， since或how long等状语连用，但在否定句中，有时可与表示一段时间的状语连用。

We haven't heard from Jane for a long time. 我们好久没有收到简的信了。（但是不可说We have heard from Jane for a long time.）

2. 延续性动词：指动作发生后还可以延续一段时间。

常用的词有：have 有;live 居住，生活;rain 下雨;sleep 睡觉;study 学习;wait 等候;work 工作等。

延续性动词可以和表示一段时间的时间状语连用。

I have already waited for Tom for two hours. 我已经等汤姆两个小时了。

3. 短暂性动词与延续性动词间的转换

leave—be away （from）; come / go （to）—be （in / at）; arrive （in / at）—be （in / at）; get （to）—be （in / at）; reach—be （in / at）; buy—have; borrow—keep; finish—be over; join—be in / be a member of; start / begin—be on; die—be dead; close—be closed; open—be open; return—be back; marry—be married; come back—be back; finish—be over; fall ill—be ill （sick）; wake up—be awake; fall asleep—be asleep; lose， leave—be gone / lost / missing等。

He has been a soldier for three years. 他参军三年了。

His father has been dead for two years. 他父亲去世两年了。

The film has been on for 5 minutes. 电影已经开始五分钟了。

We have studied English for three years. 我们（开始）学习英语已经三年了。

【随堂检测】

1. My sister ____________ English since she was 9 years old. She can talk to foreigners freely.

A. learns            B. learnt          C. has learnt        D. have learnt

2. —Does Jimmy still work as a driver？

—No. He has ____________ for two years.

A. left the company    B. gone to Shanghai    C. studied in college  D. lost his job