使用现在完成时应值得注意的问题.doc

使用现在完成时应值得注意的问题关于现在完成时的时间状语 1.现在完成时说明的是现在的情况，属于现在时。因而不能与表示过去具体时间的时间状语连用，如不可与yesterday, last week, three years ago, in 1990, at eight oclock等之类的时间状语连用。这类时间状语通常是与过去（一般）时连用。、 例如： -Has he come back yet? -Yes, he came back yesterday? 2.现在完成时通常可与表示过去不确定时间的时间状语连用，如already, yet, just, before等副词时间状语。例子见上述“主要用法”中。例如：1）I have already returned the pen to him.2）Have you washed my clothes yet? -Yes, I have just washed them.3）I have seen the man before.说明：before有时也可用于一般过去时（这与用现在完成时意思差不多），如I told you before.我早就告诉过你。 另外，already和yet有时也可用于一般现在时，如Its eight already./He isnt back yet (=He hasnt come back yet). 3.现在完成时通常可以与包括“现在”在内的表示一段时间的时间状语连用，如since., for.； ever, never, recently（最近），today, this week (year), these days (weeks, years), in/during the last/past two years, so far等。例如： 1）We have known each other since we came to the school. 2）I have collected ten stamps this weekthese weeks.3）Have you seen him these days?说明： ever, never有时也可用于一般过去时（这与用现在完成时意思差不多），如I never saw the man. 4.比较下列几组用法的区别already与yet 一般情况下，already表示“已经”，主要用于肯定陈述句，一般在句中；yet表示“已经”或“仍然，还”是用于疑问句或否定句，一般在句末。比较：1）He has already come.2）Has he come yet? 3）He hasnt come yet. already有时也可用于疑问句（句末），但不表示疑问而是表示惊讶（这与yet不同）。比较： 1）Mum, Ive done my homework.-Oh, God! Have you done your homework already?（表示惊讶） 天哪！你已经做完你的作业了？（真快！） 2）Have you done your homework yet?（表示疑问） 你做完你的作业没有？ever与yet ever与yet均可用于疑问句、否定句，但 yet表示“已经”或“仍然，还”，一般“时间上距离现在不是很远”；ever表示“曾经，以往任何时候”，“时间上距离现在可近可远”，反义词never。体会： 1）Have you ever milked a cow? 你曾经挤过牛奶吗？ -No, I never have.或No, never. 没有，从来没有过。（问可以是有生以来的经历） 2）Have you milked the cow yet? 你已经给那头牛挤过奶了吗？ -No, I havent yet.或No, not yet. （问现在说话说时的情况）for与since for和since均可引导一个时间状语，与现在完成时连用，区别如下： “for + 一段时间”，意思为“共计（时间）”；for是prep.，后面只能跟一个短语，即只能引导一个时间短语。“since + 某一时间”，意思为“自从（以来）”；since是prep.&conj.，后面可以跟一个短语，也可以跟一个句子，即既可以引导一个时间短语，也可以引导一个时间从句。 例如： 1）He has sat here since two oclock. He has sat here since he came here. 2）He has sat here for two hours.two years ago与for two years, since two years ago 三者的意思和连用的时态不一样：two years ago两年前一般过去时for two years共计两年现在完成时；一般过去时since two years ago两年来现在完成时 例如： 1）He lived here two years ago. 他两年前住在这儿。 （已有两年不住在这儿了） 2）He has lived here for two years. 他在这儿住两年了。 （两年前开始住的，一直住到现在，还可能继续住下去） 比较：He lived here for two years. 他过去（曾经）在这儿住两年了。（是哪两年不清楚） 3）He has lived here since two years ago. 两年来，他一直住在这儿。(= He has lived here for two years.) 疑问副词when不可与现在完成时连用 谈论发生在过去的事情，疑问词副词when（包括what time）不可与现在完成时连用（其它疑问副词或疑问代词可以），因为when相当于yesterday, last week, three years ago, in 1990, at eight oclock等之类的表示过去具体时间的时间状语。这类时间状语是不能与现在完成时连用的，只可与一般过去时等连用。 例如： 1）Why have you turned off the radio（收音机）？你为什么把收音机关上了？ 2）Where has he gone (to)? 他到哪儿去了？ 3）When has he gone? -He has gone yesterday. 他什么时候去的？他昨天去的。 When did he go? -He went yesterday. 关于现在完成时表示持续的用法说明 1.现在完成时表示持续时必须用持续性动词，不能用非持续性动词（即短暂性动词），因为非持续性动词是不可能表示持续的。 例如： 1）I have borrowed the book for two weeks. I have kept the book for two weeks. 2）I have bought the pen for a year. I have had the pen for a year. 3）He has put on the blue coat for five years. He has worn the blue coat for five years. 4）He has come here for two weeks. He has been here for two weeks. 5）They have begun to work in the factory since 1990. They have worked in the factory since 1990. 6）He has stood up since we came in. He has stood since we came in. 7）Mr. Wang has left Shanghai for a week. Mr. Wang has been away from Shanghai for a week. 一些常见的短暂性动词和相应的持续性动词举例如下表，仅供参考使用。还有很多很多不可能一一列出，只希望能受到启发。 短暂性动词 持续性动词 borrow keep buy have die be dead put on（穿上） wearjoin the club be in the club join the Party（入党） be in the Party或be a Party member become a Party member（党员） be a Party member或be in the Party begin to work/rain work/rain come (here) be here come back be back come to (Beijing) be in (Beijing)go (there) be there go back be back go to (Beijing) be in (Beijing)get to (Beijing) be in (Beijing)leave () 离开（） be away (from) fall ill be ill fall asleep/go to sleep be asleep go to bed be in bed get up 起床 be up get to know（开始认识） know get ready（准备好） be ready sit down sit stand up stand 2.用短暂性动词的现在完成时表示持续是错误的，其改正方法： 改动词；改句型；改时态 例如： 1）他母亲去世三年了。 His mother has died for three years. His mother has been dead for three years. （改动词） Its three years since his mother died. （改句型） His mother died three years ago. （改时态） 2）他入党二十年了。 He has joined the Party for twenty years. He has been a Party member（成员）for twenty years. He has been in the Party for twenty years. Its twenty years since he joined the Party. He joined the Party twenty years ago. 重要说明：有些短暂性动词其相应的持续性动词对你来说可能并不容易找到，这时你可以采用改句型或改时态的方法来改正。短暂性动词的现在完成时不能表示持续，是指其肯定式。但是，短暂性动词现在完成时的否定式是完全可以表示持续的，因为这时是相当于持续性动词。例如： I havent seen him for a long time.“短暂性动词的现在完成时不能表示持续”，并不代表短暂性动词没有现在完成时，只是不能表示持续罢了。例如： The fish has died. It cant move. 现在完成时和一般过去时的区别 现在完成时的基本特点是它和现在有密切的联系：或者是讲一个影响现在的动作，或者讲迄今为止这一段时间的情况。这样它不是从结果上就是从时间上和现在联系了起来。根据这个特点，我们可以判断什么时候用现在完成时、什么时候用一般过去时。例如： 1）He has written all the new words on the blackboard. 2）He has lived here since 1990. 3）He has seen the movie twice. 4）He lived here in 1990. 5）What did he say about it? 比较：What has he said to make you so angry? 6）-Have you had your lunch? -Yes, I have. -Where did you have? -I had it at home. 1.当句子里有一个表示过去具体时间如yesterday, last week, three years ago, in 1990, at eight oclock（包括when，what time）等之类的时间状语时，常要用一般过去时，因为现在完成时一般是不能与这些时间状语连用的。 例如： 1）I saw her two days agolast week. 2）When did he come? 2.当句子里含有already, yet, just, before等表示过去不确定时间的副词状语时，常用现在完成时。当然before也可用一般过去时（这与用现在完成时意思差不多）。例如：1）He has already/just left.2）The chair hasnt been mended yet. You cant sit on it.3）I have seen the man before.4）I told you before.我早就告诉过你。 3.当句子中含有一个包括“现在”在内的表示一段时间的时间状语时，如since., for.； ever, never, recently, today, this week(year), these days(weeks, years), in/during the last/past two years, so far等，常要用或常可用现在完成时。当然ever和never也可用一般过去时（这与用现在完成时意思差不多）。 例如： 1）Ive collected over 300 Chinese stamps since I came here. 2）Have you ever seen a tiger? 或Did you ever see a tiger? 另外today, this week(year), these days(weeks, years)等有时也可能与一般过去时等连用，但意义不同：用一般过去时，表示说话人单纯谈在这段时间发生的某一件事情，而不涉及它对现在造成的影响、不涉及与现在的关系。例如： The meeting