九年级英语——现在完成时用法
一、定义
现在完成时表示过去发生的某一动作持续到现在或已经完成的某一动作对现在造成的影响或结果。
二、构成
助动词have/has+动词的过去分词。
三、用法
（一）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。常与already, just, yet, ever, never等连用。例如：
Ｈave you ever seen a dinosaur?
你看见过恐龙吗？
注意：１.already常用于肯定句中；yet用于否定句句末，意为“还”，用于疑问句句末，意为“已经”。例如：
Ｉ have already finished doing my homework.
我已经做完作业了。
Ｉ haven’t decided on the menu yet,let alone bought the food.
我还没决定吃什么菜呢，更不必说买好了。
２.already用于疑问句句末时，表示惊奇、惊讶等语气。例如：
Ｈas your son gone to school already?
你的儿子已经上学了吗？
（二）表示从过去某一时刻开始，持续到现在的动作或状态。常与包括现在在内的时间状语连用，如these days,recently,lately,so far等，也常和for,since等引导的表示一段时间的状语连用。常见结构为：for+段时间；since+点时间；since+段时间＋ago；since＋从句（从句用一般过去时）。例如：
Ｈe has been in the village recently.
他最近一直在这个村子里。
Ｔhey have been away from their home for about a week.
他们离开家已经大约一周了。
I have known him since we were children.
从我们是孩子时我就认识他。
四、非延续性动词在现在完成时中的应用
非延续性动词虽可用于现在完成时，但由于其表示的动作不能持续，所以其现在完成时（只限肯定式）不能和表示一段时间的状语连用。如果句中有表示一段时间的状语，需将非延续性动词变成延续性动词。例如：
Ｂen’s grandfather has died.
本的祖父去世了。
（一）非延续性动词转换成延续性动词，主要有以下几种：
１.用相应的延续性动词。如：borrow→keep,put on→wear,come/go/become→be,buy→have,catch/get a cold→have a cold等。
２.转换成“be+名词”。如：join the Party→be a Party member,join the army→be a soldier,go to school→be a student等。
３.转换成“be+介词短语”。
如：join the army→be in the army,go to school→be in school等。
４.转换成“be+形容词或副词”。
如：begin→be on,fall asleep,be asleep,open→be open,leave→be away,finish→be over,put on→be on,die→be dead,get up→be up等。例如：
Ｈis grandfather has been dead for ten years.
他的祖父已经去世十年了。
（二）非延续性动词要和表示过去的时间状语连用，可以与“It is/has been+段时间＋since＋从句（通常用一般过去时”或“段时间＋has passed+since+从句”进行转换。例如：
Ｔhe old man died two years ago.
（=The old man has been dead for two years./It is has been two years since the old man died./Two years has passed since the old man died.）
那个老人去世两年了。
（三）非延续性动词的否定式已经成为一种可以延续的状态，因此可以和表示一段时间的状语连用。例如：
Ｉ haven’t borrowed books from the library for two weeks.
我已经有两周没从图书馆借书了。
现在完成时专练
Ⅰ.选用for或since填空。
１.She has taught herself Japanese many years.
２.The old man has lived here he was born.
３.I have known him １９８７.
４.They have lived in the village three years.
５.He has collected quite a few stamps two years ago.
Ⅱ.选用have/has been或have/has gone填空。
１.—Excuse me.Where is Amy?
—She to the teachers’ office.
２.— you ever to the Great Wall?
—Ｙes,I have.
３.My brother to Hong Kong.He there twice. ４.—Where is your mother?
—She to Shanghai.
５.—How long she at this school?
—Over three months.
Ⅲ.用括号中所给动词的适当形式填空。
１.Ｉ’m not hungry.I just （have） my supper.
２.We （not finish） doing our homework yet.
３.My grandmother （live） in this city since she （be） born.
４.The man （stay） in the house since he （come） here.
５.Her sister （go） to China.She （leave） this morning.
Ⅳ.根据汉语意思完成英语句子，每空一词。
１.我们来北京三天了。
Ｗe Beijing for three days. ２.他们离开十分钟了。
Ｔhey for ten minutes.
３.这家商店开了二十年了。
Ｔhis shop for twenty years.
４.电影开始半个小时了。
Ｔhe film for half an hour.
５.他入团两年了。
He for two years.
现在完成时专练参考答案:
Ⅰ.1.for 2.since 3.since 4.for 5.since
Ⅱ.1.has gone 2.Have,been 3.has gone,has been 4.has gone 5.has,been
Ⅲ.1.have,had 2.haven't finished 3.has lived,was 4.has stayed,came 5.has gone,left
Ⅳ.1.have been in 2.have been away 3.has been open 4.has been on 5.has been in the League/has been a League member
因篇幅问题不能全部显示，请点此查看更多更全内容