实用文档G9 GRAMMAR现在完成时I.现在完成时的概念。
①表示过去发生的动作对现在造成的影响或结果She has been ill for three days. （她病了三天了。
）②表示从过去某一时间开始一直持续到现在的动作或状态。
We've known each other since we were children. （我们从小就认识。
） I have been a member of the Party for 10 years.II.构成：”助动词have, has + 过去分词”注：规则动词的过去分词的构成与过去是相同，不规则动词的过去分词见附表。
练. 把下面变否定句、一般疑问句并作肯定和否定回答。
1. I have done my homework.否定句：_______________________________________一般疑问句：___________________________________回答：_________________________________________2. The plane has arrived.否定句：_______________________________________一般疑问句：___________________________________回答：_________________________________________III.现在完成时用法归纳1. 现在完成时表示过去发生的动作现已完成，对现在造成的影响和结果。
(此种用法谓语动词用结束性动词)实用文档如： The plane has arrived.常用的时间状语和副词：already (已经) 用于肯定句中，位置比较灵活，但通常放在have/ has 与过去分词之间如： I have already done my homework.yet (还，仍然，已经) 用于否定句和疑问句的句末。
如： Has she finished cooking yet? 他做完饭了吗？练：I have already done my homework. (变为否定句)_________________________________ever (曾经)，句中，多用于疑问句如： Have you ever been to Shanghai?never (从不) ，本身否定；before (以前)，句尾，独立用；just (刚刚)，用于肯定句中，常用在助动词和过去分词之间。
如：I have just heard the news. 我刚刚听到消息。
2. 完成时可用于表示某时间段里完成的动作，常与today, these days, recently等时间状语连用。
如：Have you seen her these days? 译： ______________Have you been to the library today? 译：____________Have you read the book recently? 译：______________3.现在完成时表示过去已经开始，持续到现在，可能延续到将来的动作和状态。
常与表示过去某一时刻延续到现在的一段时间状语连用。
如：a.for + 一段时间：for two hoursb.since + 时间点：since 1999, since last yearc.since + 一段时间+ ago: since two days agod.since + 从句（用过去时）e.up to now, till now, until now, so farf.in the past two years, in the last few daysg.recently, latelyhas taught math for five years. 如： Miss Zhaohas worked in the shop since 1990.His motherhave lived in London since three years ago. The Greens[注]：其中在a,b,c,d 这四种结构中，谓语动词必须为延续性动词。
如： I have had this book for one and a half years. (这本书我已买了一年半了！)buy不能用4. 短暂性动词怎样和表示一段时间的状语连用。
只表示一也叫做终止性动词、瞬间动词或非延续性动词，英语中的短暂性动词，常见的短暂性动词有：时的动作，在肯定句式中不能与表示延续的时间状语连用。
begin, marry, die, give, find, buy, arrive, stop, join, leave, go, come,等。
start, borrow, close, open, lend) eg. I have bought this book for three months. (×非延续性动词与一段时间连用时可采用下列三种方法：实用文档（1）将非延续性动词转化为延续性动词。
leave- have (has) been away from close- be closedjoin- have (has) been (in) begin/start- be onbuy- have (has) had go- be theredie- have (has) dead finish- be overcome (arrive)- have (has) been here borrow- have (has)keptbegin to work- have (has) worked open- have (has) been openget up- have (has) been up put on – have (has) on come back- have (has) been back gone (left)- been away joined – been got to know – known （2）时间状语的变化：把表时间的状语“for…”变为“数词+ 时间名词+ago”的短语形式。
（即：将时间状语改为过去时间，并用一般过去时代替现在完成时）如：他参军五年了。
（判断正误）He has joined the Army for five years. ( )He has been in the Army for five years. ( )He joined the Army five years ago. ( )他离开济南三年了。
He has left Ji'nan for three years. ( )He has been away from Ji'nan for three years.He left Ji'nan three years ago.(3) 句子模式的变化。
用句型“It is + 一段时间+ since从句”（从句中的谓语动词用非延续性动词的一般过去式表示）如：The old man died two years ago.= The old man has been dead for two years. = It is two years since the old man died.5. have been to/ have gone to/ have been in 三种结构的区别（1）have been to 去过某地(现已离开)，可以与ever, never, once, twice等连用。
（2）has gone to 去某地了，说话时某人已离开此地，在去某地的路上或已在某地，总之现在还未回来。
此句型一般用于第三人称。
（3） have been in 表示已在某地呆了多久，若该地为小地方则用at。
翻译：你以前去过北京吗？___________________________吉姆已经去了伦敦。
___________________________格林一家在中国已经两年了。
_____________________6. 现在完成时与一般过去时的区别：(1) 侧重点不同：现在完成时是与现在有关的时态，属现在时态范畴，它侧重于过去的动作对现在造成的影响。
而一般过去时是一种过去时态，侧重于表示过去的动作，与现在无关。
如：Yesterday I went to the zoo. (仅说明昨天去了动物园，与现在无关)Li Lei has read the book. (说明李磊了解那本书的内容)（2）连用的时间状语不同：一般过去时常与ago, yesterday, last…, in 2000, just now等连用。
而现在完成时与already, yet, still, just, so far, in the实用文档last/ past…, before, ever, never, since…, for…等时间状语连用。
[注] 现在完成时不可与yesterday, last week, two days ago等过去时间状语连用。
被动语态语态是动词的一种形式，它表示主语和谓语的关系。
语态有两种：主动语态和被动语态。
如果主语是动作的执行者，或者是说动作是由主语完成的，要用主动语态；如果主语是动作的承受者，或者是说动作不是由主语而是由其他人完成的，则用被动语态。
一、被动语态各时态构成表Our classroom is cleaned everyday.A new shop was built last year.This book has been translated into many languages.A new hospital will be built in our city.Young trees must be watered often.My bike is being repaired by Tom now.There are twenty more trees to be planted.二、主动句变为被动句所遵循的4个步骤：1.把原主动句中的宾语变为被动句的主语2.把动词变为被动形式即be +过去分词，并注意其人称和数随主语的变化，而动词的时态则保持不变。
实用文档3.原主动句的主语如需要则放在by后面以它的宾格形式出现（注代词的宾格），如不需要则可省略。
4.其它的成分（定语、状语）不变。
三、不用被动语态的情况1) 不及物动词或动词短语无被动语态（即多数的瞬间动词）：appear, die(死亡),disappear（消失）, end (vi. 结束), fail, happen, last, lie, remain, sit, spread, stand比较： rise, fall, happen是不及物动词；raise, seat是及物动词。