1、表示堅(jiān)決的命令，可譯為“必須”。

　　(1)This naughty boy is to stay here until the class is over.這個(gè)淘氣的男孩必須在這里站到下課。

　　(2)No one is to enter this building without the permission of the security guard.未經(jīng)保安人員的允許，任何人都不得進(jìn)入這棟樓。

　　2、表示“計(jì)劃”或“安排的事項(xiàng)”。

　　(1)Betty is to be married soon.貝蒂很快就要結(jié)婚了。

　　(2)An insurance agent is to meet us this afternoon.今天下午會(huì)有一個(gè)保險(xiǎn)代理人來跟我們見面。

　　3、表示“可能性”。

　　(1)Are you to pay the debt for your wife?你會(huì)不會(huì)幫你的妻子還債？

　　(2)The lovely puppy is nowhere to be found.哪兒也找不到這只可愛的小狗。

　　4、表示“意圖”“決心”或“打算”。

　　(1)If you are to be there on time, you had better hurry.要想準(zhǔn)時(shí)到達(dá)那兒，你最好快點(diǎn)。

　　(2)If all of us are to remain friendly, we must be sincere with one another.要想保持友誼，我們都必須真誠(chéng)相待。

　　5、表示“應(yīng)該”。

　　(1)You have done so well. You are to be rewarded.你做的很好，你應(yīng)該受到獎(jiǎng)賞。

　　(2)Such nasty questions are to be avoided.你應(yīng)該避免這種下流的問題。

　　(3)You are to call the police.你應(yīng)該報(bào)警。

　　6、表示“注定”“不可避免”“必然會(huì)發(fā)生”。

　　(1)Anne was wondering what was to become of her boy friend, Tommy.安妮不知道她的男朋友托米會(huì)出什么事。

　　(2)The murderer was sentenced to life imprisonment and was never to see his family again.殺人犯被判終身監(jiān)禁并且永遠(yuǎn)不能和家人見面。

　　(3)She did not think too much of her unkind acts.However，they were to be harmful to herself，too.她對(duì)她不友好的行為并沒有想太多，然而，這些行為必將給她帶來不利。

　　(4)Tom wasn’t worried about his head injury,but it was to be troublesome for him later.湯姆不擔(dān)心他頭部的傷，但是以后這損傷必將給他帶來麻煩。

　　(5)You are to answer for what you have done.你必將為你所做的事承擔(dān)后果。

　　7、用于虛擬語(yǔ)氣，表示一種假設(shè)。

　　(1)If I were to do it, I would do it well.這件事如果我來做，我會(huì)做好它。

　　(2)Even if you were to take a taxi now, you would not be able to arrive at your destinaton on time.現(xiàn)在即使坐出租車，你也不會(huì)準(zhǔn)時(shí)到達(dá)目的地的。

　　8、有“期待將來”的意思。

　　(1)The actual usefulness of the newly invented equipment is still to be determined.這種新發(fā)明出來的設(shè)備的實(shí)用性如何還有待觀察。

　　(2)Henry's appointment with the accountancy firm is yet to be confirmed.亨利與這家會(huì)計(jì)事務(wù)所的約定還有待確認(rèn)。