英语现在完成时时态语法知识讲解(2)

　　用于现在完成时的句型

　　1)It is the first / second time…. that…结构中的从句部分，用现在完成时。

　　It is the first time that I have visited the city.

　　It was the third time that the boy had been late.

　　2)This is the… that…结构，that 从句要用现在完成时.

　　This is the best film that I've (ever) seen.

　　这是我看过的最好的电影。

　　This is the first time (that) I've heard him sing.　这是我第一次听他唱歌。

　　典型例题

　　(1) ---Do you know our town at all?

　　---No, this is the first time I ___ here.

　　A. was　 B. have been　 C. came　 D. am coming

　　答案B. This is the first time 后面所加从句应为现在完成时，故选B。

　　(2) ---Have you ____ been to our town before?

　　---No, it's the first time I ___ here.

　　A. even, come　 B. even, have come　　C. ever, come　 D. ever, have come

　　答案D. ever意为曾经或无论何时，反意词为never，此两词常用于完成时。 This is the largest fish I have ever seen. It is / was the first time +that-clause 的句型中，从句要用完成时。

　　注意：非延续性动词的否定形式可以与表示延续时间的状语连用。即动作不发生的状态是可以持续的。

　　(错)I have received his letter for a month.

　　(对)I haven't received his letter for almost a month.

　　现在完成时的语法知识

　　【用一般过去时代替完成时】

　　1) 构成will / be going to do sth.

　　2) 概念

　　a. 状态完成：表示某事继续到将来某一时为止一直有的状态。

　　b. 动作完成：表示将来某一时或另一个将来的动作之前，已经完成的动作或一获得的经验。

　　They will have been married for 20 years by then.

　　You will have reached Shanghai by this time tomorrow.

　　【一般现在时代替完成时】

　　1) 有些动词用一般现在时代替完成时：

　　hear, tell, learn, write , understand, forget, know, find , say,　remember.

　　I hear (= have heard) he will go to London.

　　I forget (=have forgotten) how old he is.

　　2) 句型 " It is … since…"代替"It has been … since …"

　　3) It is (= has been) five years since we last met.

　　【现在完成时转换成一般过去时】

　　现在完成时可以转化成一般过去时，还可以转化成“It is/has been +时间段+since从句(用一般过去时)”等句型。

　　e.g. Jim has been back for a month. 吉姆已经回来一个月了。 = Jim came back a month ago. 吉姆一个月前就回来了

　　= It is/has been a month since Jim came back. 自吉姆回来已经有一个月了。 = A month has passed since Jim came back. I have kept the book for two days. = I borrowed the book two days ago.

　　= It is / has been two days since I borrowed the book. = Two days has passed since I borrowed the book.

　　【延续动词与瞬间动词】

　　1) 用于完成时的区别

　　延续动词表示经验、经历; 瞬间动词表示行为的结 果，不能与表示段的时间状语连用。

　　He has completed the work.　　他已完成了那项工作。 (表结果)

　　I've known him since then.　　我从那时起就认识他了。(表经历)

　　2)用于till / until从句的差异

　　延续动词用于肯定句，表示"做……直到……" 瞬间动词用于否定句，表示"到……，才……"

　　He didn't come back until ten o'clock.

　　他到10 点才回来。

　　He slept until ten o'clock.

　　他一直睡到10点。

　　典型例题

　　1. You don't need to describe her. I ___ her several times.

　　A. had met　B. have met　 C. met　D. meet

　　答案B. 首先本题后句强调对现在的影响，我知道她的模样，你不用描述。再次，several times告知为反复发生的动作，因此用现在完成时。

　　2.---I'm sorry to keep you waiting.

　　---Oh, not at all. I ___ here only a few minutes.

　　A. have been　 B. had been　 C. was　D. will be

　　答案A. 等待的动作由过去开始，持续到现在，应用现在完成时。

　　【比较since和for】

　　Since 用来说明动作起始时间，for用来说明动作延续时间长度。

　　I have lived here for more than twenty years.

　　I have lived here since I was born..

　　My aunt has worked in a clinic since 1949.

　　Some new oilfields have been opened up since 1976.

　　I have known Xiao Li since she was a little girl.

　　My brother has been in the Youth League for two years.

　　I have not heard from my uncle for a long time.

　　注意：并非有for 作为时间状语的句子都用现在完成时。

　　I worked here for more than twenty years.

　　(我现在已不在这里工作。)

　　I have worked here for many years.

　　(现在我仍在这里工作。)

　　小窍门：　当现在完成时+一段时间，这一结构中，我们用下面的公式转化，很容易就能排除非延续动词在完成时中的误使。

　　1)　(对) Tom has studied Russian for three years.

　　= Tom began to study Russian three years ago, and is still studying it now.

　　2)　(错) Harry has got married for six years.

　　= Harry began to get married six years ago, and is still getting married now.

　　显然，第二句不对，它应改为 Harry got married six years ago.　或 Harry has been married for six years.

　　【延续性与非延续性动词在现在完成时态中的使用】

　　(1)有一些动词是瞬间动词，也叫非延续性动词，这些动词一发生就结束了，常见的有：come, go, arrive, reach, leave, begin, start, buy, join, die, borrow, get up, become, open, stop等。这些动词虽然可以用于现在完成时(说明某个动作的结果还存在)，但由于它们不能延续，因此不能跟表示一段的时间状语连用。(也即现在完成时的第二个基本用法中不能使用非延续性动词)。

　　e.g. Jim has come back. (正) 吉姆已经回来了。

　　Jim has come back for a month. (误) come back的动作不能延续一个月，因此错误。

　　(2)瞬间动词不可以用于有段时间的现在完成时态中，因此，若要解决这一问题，就应把它改为相应的延续性动词或短语，主要有以下几种：

　　①用相应的延续性动词

　　如： buy → have borrow → keep come/go/become → be put on → wear catch a cold → have a cold ②转换成be+名词

　　如： join → be a member of go to school → be a student ③转换成be+形容词或副词

　　如： die → be dead leave → be away begin → be on finish → be over fall asleep — be asleep open → be open get up → be up close → closed ④转换成be+介词短语

　　如： come to/go to/arrive in (at)/get to/reach …→ be in/at… join the army → be in the army(军队)

　　e.g. I have borrowed the book. 我已经借了那本书。

　　I have kept the book for two days. 我已经借那本书两天了。

　　Jim has joined the band. 吉姆已经加入那乐队了。

　　Jim has been a member of the band for a month. 吉姆已经加入那个乐队一个月了。

　　His grandfather has died. 他祖父已经死了。

　　His grandfather has been dead for 2 years. 他祖父已经死了两年了。

　　My father has arrived in China. 我父亲已经到达中国了。

　　My father has been in China for a week. 我父亲已经在中国一个星期了。

　　(3)在否定句中，非延续性动词也可以与时间段连用。

　　e.g. I haven’t borrowed books from the library since last year. 自去年以来我就没有在图书馆借过书。

　　Jim hasn’t come back for a year. 吉姆已有一年没回来了。