现在完成时

一、现在完成时

现在完成时的三种用法：

1)表示一个已经发生但对现在情况有所影响的动作，例如：

He has gone to the town. 他进城去了。（说明他现在不在这里）

Someone has turned off the light. 有人把灯关了。（说明现在房间里是黑的）

We have planted some trees around the building. 我们在楼周围种了些树。（说明房子周围现在已经有树了）

2)表示过去某时到现在这段时间中发生的事情，例如：

We have learned six hundred words this term. 我们这学期已经学了600个单词了。（说明学期开始到现在这段时间发生的事情）

They have built hundreds of houses in the past three years. 三年来他们修建了千百座房子。Great changes has taken place in china since liberation.解放以来中国发生了巨大的变化。

3)表示一个由过去某时继续到现在的动作或者状态，例如：

I have lived here for four yeas. 我在这里住四年了。

He has been in the school since 2014.他从2014年就在这所学校里。

注：只有少数延续性动词才适应第三种情况，如：live, work, study, wait, be等。

终止性动词表示某一动作的完成，因此可以用于现在完成时，例如：

The train has arrived .火车到了。

Have you joined the computer team?你加入电脑小组了吗？

终止性动词表示的动作极其短暂，不能持续，不能和表示一段时间的状语连用，例如：误：he has died for 3 years.

正：he has been dead for 3 years.

正：he died 3 years ago.

正：it is 3 years since he died.

正：3 years has passed since he died.

将终止性动词转化成延续性动词：

Leave---be away borrow----keep buy---have begin/start---be on die--be dead Move---live in finish--be over join--be in/be a member of open----keep sth open

Fall ill--be ill get up--be up catch a cold--have a cold

二、构成

现在完成时由“助动词have(has) 加过去分词”构成。

规则的动词过去分词和过去形态相同，如：

过去式过去分词

Live lived lived

Study studied studied

Plan planned planned

见课本P136

三、现在完成时和一般过去时的比较 一般过去时表示过去发生的事情，现在完成时也表示过去发生的事情，但是两者表示的重点不同。一般过去时只表示过去发生事情本事，不涉及与现在的关系。现在完成时则强调过去发生的事情对现在的影响，主要说明现在的情况。

有时同一个动作，由于说话目的不同，可能使用不同的时态，例如：

Have you had your breakfast? 如果还没吃，就在这里吃 Yes, i have.

Where did you have your breakfast? 只是吃早饭这个动作 I had it in town.

标志词：already, yet, just, never, ever 表示不定时间的状语： He has just come back from the USA. She hasn ’t finished her work yet.

表示包括现在在内的过去一段时间的状语：today, this morning, this week, since 1998, for a long time, in the past few years 等。

We have had 2 classes this morning. 说这话时还是上午。 They have been close friends ever since 2012. She has made great progress in the past 3 months.

四、have been in, have been to 与have gone to 1.、have(has) been in 表示“在某地呆多长时间”，常与表示一段时间的状语连用，如：since, for, how long 等。例如：

Mr. Brown has been in Shanghai for three days. 布朗先生来上海已经有三天了。 此外还有这些搭配： have been here (there) /at home (school) /on the farm have been here (there) / abroad

2、have(has)been to表示“曾经去过某地”，现在已经不在那里了。可与just, ever, never等连用，例如：I have just been to the post office. 我刚才去邮局了。

Mary has never been to the Great Wall. 玛丽从未去过长城。

Have you ever been to Hangzhou? 你曾经去过杭州吗？

have(has) been to 后面可接次数，表示去过某地几次。例如：

I have been to Beijing three times. 我去过北京三次。

They have been to that village several times. 他们去过那个村庄好几次了。

4、have(has) gone to 意为“到某地去了”，表示到了某地或正在去某地的途中。总之，说话时该人不在现场，一般不用第一、第二人称代词作句子的主语。

例如：----Where is Tom? ----He has gone to the bookshop. 汤姆在哪里？他到书店去了。Jack Johnson has gone to London. 杰克.约翰逊到伦敦去了。