2009年12月大學(xué)英語(yǔ)四六級(jí)考試語(yǔ)法精要(四)

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　　時(shí)態(tài)

　　1. 現(xiàn)在完成時(shí)、過(guò)去完成時(shí)以及將來(lái)完成時(shí)之間的區(qū)別

　　1) 現(xiàn)在完成時(shí)：

　�、� 構(gòu)成：have / has +過(guò)去分詞

　�、� 語(yǔ)法意義及要點(diǎn)：

　　A. 現(xiàn)在完成時(shí)表示一個(gè)過(guò)去開(kāi)始的狀態(tài)或動(dòng)作持續(xù)到現(xiàn)在并可能繼續(xù)持續(xù)下去，常同表示一段時(shí)間的狀語(yǔ)連用。如so far, up to now, since, for a long time等。

　　--He has worked as a teacher for many years.

　　--Up till now, nothing has gone wrong.

　　B. 現(xiàn)在完成時(shí)表示一個(gè)過(guò)去發(fā)生的對(duì)現(xiàn)在仍有影響的動(dòng)作或事件。常與不確定的過(guò)去時(shí)間狀語(yǔ)連用，如yet, just, before, recently等;也同表示頻度時(shí)間狀語(yǔ)連用，如often, ever, never, sometimes, several times等;還可同包括現(xiàn)在時(shí)間在內(nèi)的時(shí)間狀語(yǔ)連用，如now, today, this morning等。但不能同特定的過(guò)去時(shí)間狀語(yǔ)連用(last year , in 1997等)。

　　--I have never learned Japanese before.

　　--We have been quite busy lately (recently).

　　C. 在時(shí)間或條件狀語(yǔ)從句中，當(dāng)表示將來(lái)完成時(shí)的意義時(shí)，要用現(xiàn)在完成時(shí)來(lái)代替將來(lái)完成時(shí)。

　　--We’ll start at 5 o’clock if it has stopped raining by then.

　　--I shall go to see you when I have finished my homework.

　　Note: 行為不能持續(xù)的瞬間動(dòng)詞(Instantaneous Verb), 如arrive, begin, come, go, start, leave, die, join等通常不能用于這一語(yǔ)法意義，即該類(lèi)動(dòng)詞在現(xiàn)在完成時(shí)中不能與表示一段時(shí)間的狀語(yǔ)連用。

　　--He has joined the army for five years. (誤)

　　--He has been in the army for five years. (正)

　　2) 過(guò)去完成時(shí)：

　�、� 構(gòu)成：had +過(guò)去分詞

　�、� 語(yǔ)法意義及要點(diǎn)：

　　過(guò)去完成時(shí)表示某一動(dòng)作或情況發(fā)生在過(guò)去某一時(shí)刻之前并持續(xù)到該時(shí)刻。

　　--David and Jenny had known each other for a long time before their marriage.

　　--They had got everything ready before the party began.

　　Note: 與現(xiàn)在完成時(shí)截然不同的是過(guò)去完成時(shí)可以與表示具體過(guò)去的時(shí)間狀語(yǔ)連用。

　　--He said that he had seen her the day before yesterday.