现在完成时的用法现在完成时的概念及构成形式现在完成时.ppt

现在完成时的用法 现在完成时的概念及构成形式： 现在完成时表示的是过去的动作对现在的影响或过去的动作持续到现在。 其结构为：have/has + 动词的过去分词。 否定形式：havent/hasnt + 动词的过去分词； 疑问形式：Have/Has you, hedone ? 回答为： Yes, I have/No, I havent. 规则动词的过去分词形式与动词的过去式形式相同，如：finished, stayed, planned, arrived, studied等；不规则动词的过去分词需要参照附录中的去加以记忆。但大多数不规则动词的过去分词与过去式的形式相同。,现在完成时的用法： 过去的动作对现在造成的影响和结果。它常与already(已经), ever（曾经）, just（刚刚）, never（从未）, yet（还，尚）, recently（最近）等副词连用；也可以与in the last few days/weeks/years/, these days/weeks/years/, so far（到目前为止）等时间状语连用。在这些副词中，already与yet是相对应的，already用于肯定句中，yet用于否定句中。 E.g. Weve already finished our work. / We havent finished our work yet. He has just arrived here. I have never been to Britain. / Have you ever been to Britain? Ive read a new book recently. / Shanghai has developed very quickly in the past few years.,过去开始的动作持续到现在，它往往和for, since构成的时间状语连用。for用于一段时间之前，而since用于某一特定的时刻之前。 E.g. Diana has been in Shanghai for three years. I havent seen you for a long time. I have studied English for six years. / I have learned English since 2002. Great changes have taken place in Shanghai since 1993. 句中有for+一段时间或since+时间点，则句中的谓语动词要用延续性动词。以下是一些短暂性动词对应的延续性动词： arrive be in, begin be on, borrow keep, buy have, die be dead finish be over leave be away from, join be in / be a member fall asleep be asleep catch a cold have a cold,表示反复性和习惯性的动作，它常与表示次数的副词连用，如：twice, three times, several times. E.g. I have seen the film twice. / Ive read Sherlock Holmes three times. 4、have gone to / have been to 的区别： have gone to 表示去了某地还没回来。（在去得路上，或在那个地方） have been to表示去了某地已经回来了。（已经不在所说的那个地方） E.g. Where has your father gone? He has gone to Beijing. I have been to Beijing twice.,现在完成时与一般过去时的区别： 1、现在完成时表示的是过去的动作对现在造成的影响或结果，强调的是现在的状况。所以不能和表示过去的时间状语连用。而一般过去时只是单纯地表示过去的动作或状态，和目前的状况无关，它往往和表示过去的时间状语连用。如：ago, yesterday, last week, in the past, just now. E.g. A: Have you seen the film yet? B: Yes, I have. A: When did you see the film? B: I saw it yesterday afternoon. 2、现在完成时中的谓语动词是延续性动词时，必须和表示一段时间的状语连用。若谓语动词是短暂性动词，则不能和表示一段时间的状语连用。 E.g. I borrowed the book two days ago. I have kept the book for two days. His grandpa died three years ago. His grandpa has been dead for three years. 3、for的时间状语可用于现在完成时，也可用于一般过去时的句子中，但含义有所区别： E.g. He has lived