高中語法專練：iv. shall, should, ought to

iv. shall, should, ought to

1. shall的基本用法：

構(gòu)成將來時態(tài)，單純表示將來的動作。

I shan't be coming back today.

我今天不會回來。

We shall read about this tomorrow.

我們明天將要讀到有關(guān)這件事的文章。

2. shall在運用中需要注意的問題：

1）在疑問句中用于第一、三人稱，表示向?qū)Ψ秸髑笠庖娀蛱岢稣埱蟆?/p>

Shall I open the door for you?

我給你開門好嗎？

When shall he be able to leave the hospital?

他何時能出院呢？

2）在陳述句中多用第二、第三人稱作主語，表示說話人的一種情感或意志（如表示命令、允許、決心、警告、威脅等）或者法律規(guī)章的規(guī)定。

You shall have a new i-phone on your birthday.

你的生日時將得到一款新i-phone手機。

You shall fail if you don't work harder.

你若是不更努力，就會失敗。

He shall have the book when I finish reading it.

我一讀完他就可以拿到這本書。

3. should的基本用法

1）should可用作shall的過去式。只適用于直接引語變間接引語，構(gòu)成過去將來時。

I said I should be there before dark.

我說我將在天黑前到那里。

—I shall go for the holiday next week.

—You said you should go for a holiday the next week, right?

——我下周要去度假。

——你說你下周要去度假，對嗎？

2）表示應該做，而且有一種道義上的責任。也有表示估計或推測之意。

I should help him because he is in trouble now.

我應該幫助他因為他正處于困境中。

The report was written after careful investigation, so it should be reliable.

這個報告是仔細調(diào)查后寫出來的，因此它應該是可靠的。

4. should在運用中需要注意的問題：

1）在一堅持（insist），二命令（order, command），三建議（advise, suggest, propose），四要求（ask, demand, require, request）等動詞后跟的賓語從句中和名詞后跟的表語從句及同位語從句中，用“should +動詞原形”（should經(jīng)常省略）的形式。

He suggested that it (should) be done right now.

他建議立刻干這件事。

He gave the orders that the work (should) be started at once.

他發(fā)出命令這項工作應該立刻開始。

2）should可表示“萬一”，用于if引導的非真實條件句中，虛擬語氣表示對將來的事情的猜測。

If it should rain tomorrow, we would not go to the botanical garden.

如果明天萬一下雨，我們就不會去植物園了。

3）表示驚異、贊嘆、不滿意等情緒，也表示比較難以相信或不應該發(fā)生的事情。

I am surprised that he should eat so little every day.

我很吃驚他每天竟然吃這么少。

You can't imagine that a well-behaved gentleman should be so rude to a lady.

你不能想像一個舉止文雅的紳士竟然對一位女士這么粗野。

4）用在“It is +形容詞(natural, necessary, important, essential, right, impossible, strange）+ that + ... should + do”結(jié)構(gòu)中，表示理所當然、奇怪、必要、驚異等。

It was natural that he should feel hurt.

他覺得受到了傷害這很自然。

It is strange that he should be assigned to do the work.

很奇怪他竟然被分配做這項工作。

5）用于so that, lest, in case等引導的從句中。

Take an umbrella in case it should rain tonight.

帶把雨傘吧以免今天夜里有雨。

6）should be doing表示推測，意為“應該正在”，而實際上沒有。

You shouldn't be reading a novel. You should be reading a textbook in class.

你不應該在讀小說，你應該在課堂上讀課本。

7）should have done = be to have done = ought to have done = be supposed to have done，表示過去應該做某事而實際沒做。

It's ten o'clock. She should have arrived in the office by now.

現(xiàn)在十點了，她現(xiàn)在本來應該到辦公室了。

8）shouldn't have done表示過去不該做某事而實際上做了某事。

You shouldn't have got up so early； it is still early.

你不該起床那么早，天還黑著呢。

5. ought to的基本用法

1）表示推測、估計、可能性、（按道理）應該、應當。

You ought to start at once if you want to catch your train.

如果你想趕上火車就應該馬上動身。

2）表示勸告、建議。

You ought to be reviewing your lessons now.

你現(xiàn)在應該在復習功課了。

6. ought to在應用中需注意的問題：

1）ought to have done = should have done，表示本該做某事而沒有做。

I ought to have helped her, but I never could.

我本來應該幫助她，但是我從來沒能夠幫。

2）ought to be doing = should be doing，表示現(xiàn)在應該正在做某事。

It is 12 o'clock, he should be having lunch now.

現(xiàn)在是12點，他應該正在吃午飯。

3）oughtn't have done = shouldn't have done，表示本不該做某事而做了。

You oughtn't have spoken to her in that way.

你本不該對她那樣說話的。

4）should = ought to，表示應該，但是should多用來談自己的主觀看法，ought to用來表示客觀看法，即根據(jù)法律、義務和規(guī)定來談論“應該或者不應該”。

The diet should be maintained unchanged for about a year.

這樣的飲食應保持約一年不變。

One ought not to cross the street against the red light.

人們不該在紅燈時過馬路。

專項練習

1. My sister _______ here by now, for she took the early train.

A. must arrive

B. can arrive

C. may arrive

D. ought to have arrived

2. You went to the wrong shop. You ought _______ to the shop next to the cinema, but you went to the shop by the Post Office.

A. go

B. to go

C. have gone

D. to have gone

3. Tom ought not to _______ me your secret, but he meant no harm.

A. have told

B. tell

C. be telling

D. having told

4. There _______ be any difficulty about passing the road test since you have practised a lot in the

driving school.

A. mustn't

B. shan't

C. shouldn't

D. needn't

5. Mr White _______ at 8:30 for the meeting, but he didn't show up.

A. should have arrived

B. should arrive

C. should have had arrived

D. should arrive

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