專四語法總結 專四語法總結

　　時態(tài)、語態(tài)需要掌握的要點：

　　1.表達將來時的形式：

　　(1)在時間、條件、讓步從句中，一般現在時代替將來時，但要注意區(qū)別從句的類型，如：

　　I’ll tell him when you will ring again. 我告訴他你什么時候再來電話。(賓語從句)

　　比較：I’ll tell him when you ring again.你再打電話時我告訴他。(狀語從句)

　　(2)在make sure, make certain, see (to it) 后的that從句中，謂語動詞用一般現在時代替將來時，如：

　　See to it that you include in the paper whatever questions they didn’t know the answer to last time.

　　(include 不能用will include或其他形式)

　　2.完成時是時態(tài)測試的重點，注意與完成時連用的句型和時間狀語：

　　(1)by/between/up to/till +過去時間、since、by the time/when +表示過去發(fā)生情況的從句，主句用過去完成時。

　　如：We had just had our breakfast when an old man came to the door.

　　Between 1897 and 1919 at least 29 motion pictures in which artificial beings were portrayed had been produced.

　　(表示1919年時已發(fā)生的情況)

　　(2)by +將來時間、by the time/ when +謂語動詞是一般現在時的從句，主句用將來完成時。如：

　　By the time you arrive in London, we will have stayed in Europe for two weeks.

　　I hope her health will have improved greatly by the time we come back next year.

　　(3)by now、since +過去時間、in/during/for/over/the past/last few(或具體數字)years/days/months，主句用現在完成時,如：

　　The changes that had taken place in air travel during the last sixty years would have seemed completely impossible to even the most brilliant scientists at the turn of the 19th century.

　　但在it is +具體時間since/before這一句型中，主句更多的時候不用完成時。

　　It is four years since John left school.

　　(4)在It is the +序數詞/形容詞最高級+that的定語從句中，謂語動詞常用現在完成時。如：

　　It isn’t the first time that I have found myself in an embarrassing situation.

　　(5)在no sooner…than…, hardly/scarcely…when…句型中，主句常用過去完成時。

　　3.完成進行時指動作在完成時的基礎上還要繼續(xù)下去。如：

　　The company has been promising a rise in salary for ages, but nothing has happened.

　　時態(tài)、語態(tài)答題思路：

　　(1)先根據選項的區(qū)別點確定考題要點為時態(tài)，然后回到題句中尋找給出的或暗示的時間狀語，縮小選擇范圍，進而選出正確答案;

　　(2)根據謂語動詞與句子主語或非謂語動詞與其邏輯主語的關系，確定句子是主動語態(tài)還是被動語態(tài)。