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關(guān)閉窗口 “be+不定式”用法詳解
“be+不定式”是一個(gè)很有用的結(jié)構(gòu)，本文擬對(duì)該結(jié)構(gòu)的用法作一詳細(xì)歸納。
一、表示將來或預(yù)計(jì)
I don’t know what is to happen to us. 我不知道我們會(huì)發(fā)生什么事。
I went to have a look at the room where I was to talk that afternoon. 我去看了一下地方，當(dāng)天下午我要在那里講話。
It was 1491. Columbus was to reach America a year later. 那是1491年，一年后哥倫布到達(dá)了美洲。
說明：當(dāng)該結(jié)構(gòu)中用了still或yet時(shí)，其將來意義更加突出。如：
The worst is still to come. 還有最糟糕的事情要發(fā)生。
The most severe weather is yet [still] to come. 最惡劣的天氣還沒有到。
The best item on the programme is still to come. 最好看的節(jié)目還在后頭。
注意，該結(jié)構(gòu)表示將來的用法是有限的，原則上，只有當(dāng)表示的動(dòng)作為人所控制時(shí)才可使用它來表示將來，否則就是錯(cuò)的。如可說 I’m going to play tennis，也可說 I’m to play tennis，因?yàn)槠渲械?/FONT> play tennis是可以人為控制的。而在以下各例中，其中的動(dòng)作均不能為人所限制，所以going不可省略：
He’s going to be fat. 他要發(fā)胖了。
There is going to be a storm. 要下暴風(fēng)雨了。
You’re going to break that chair. 你會(huì)把那把椅子弄壞的。
二、表示計(jì)劃或意圖
They are to be married. 他們打算結(jié)婚。
We are to be married in June. 我們計(jì)劃在6月結(jié)婚。
說明：該結(jié)構(gòu)也可用于條件狀語(yǔ)從句。如：
If I’m to be there on time, I must leave at once. 如果我要想準(zhǔn)時(shí)趕到那兒，我就必須馬上動(dòng)身。
If we are to succeed in this enterprise, we shall need to plan everything very carefully. 如果我們想要在這項(xiàng)事業(yè)上取得成功，我們就需要把一切都仔細(xì)計(jì)劃好。
另外，若表示過去未曾實(shí)現(xiàn)的想法或意圖，其中的不定式則用完成式。如：
We were to have gone away last week, but I was ill. 我們本打算上周走的，但是我病了。
I was to have started work last week, but I changed my mind. 我本該上周開始工作的，但我改變了主意。
比較：
He was to go. 當(dāng)時(shí)他是要去的。(至于最后去沒去，不得而知)
He was to have gone. 他本來是要去的。(但實(shí)際上卻沒有去)
三、表示責(zé)任或義務(wù)
You are to report to the police. 你應(yīng)該報(bào)警。
I am to inform you that... 我有義務(wù)(我受人之托)通知你……
She is to be in class at 9 am. 她應(yīng)該上午9點(diǎn)到課堂。
四、表示命令或規(guī)定
You are not to smoke here. 此處禁止吸煙。
All staff is to wear uniforms. 全體工作人員必須穿制服。
Visitors are to leave when the bell rings. 來訪者必須在鈴響時(shí)離開。
You are to do your homework before you watch TV. 你得做完了作業(yè)才能看電視。
She can go to the party, but she’s not to be back late. 她可以去參加聚會(huì)，但不能晚回來。
No one is to leave this building without the permission of the police. 未經(jīng)警務(wù)人員允許，任何人不得擅自離開這座房子。
五、表示目的或用途
A knife is to cut with. 刀子是用來切東西的。
The telegram was to say that she'd be late. 電報(bào)是說她可能晚到。
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