•[+ (that)] Are you absolutely certain (that) you gave them the right number?你敢肯定你给他们的号码没错吗？

•I feel certain (that) you're doing the right thing.我确信你做得对。

•You should make certain (that) everyone understands the instructions.你应该确保大家都能听懂指令。

•The police seem certain (that) they will find the people responsible for the attack.警方似乎确信他们会查出谁须对这次袭击事件负责。

•[+ question word] I'm not certain how much it will cost.我不能确定这要花费多少钱。

•He was quite certain about/of his attacker's identity.他对袭击他的人的身份十分肯定。

•One thing is certain - she won't resign willingly.有一点是肯定的——她不会心甘情愿地辞职。

•I don't know for certain if she's coming.我不能肯定她是否会来。

•I can't say for certain how long I'll be there.我说不准我在那里会留多久。

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•[+ to infinitive] The population explosion is certain to cause widespread famine.人口激增必然会引起大范围的饥荒。

•Oil prices are certain to rise following the agreement to limit production.限制石油生产的协议签订后油价必然会上涨。

•After all his hard work, he's certain to pass his exams.他这么用功，一定会通过考试的。

•The team looks almost certain to win the match.这支球队看上去几乎准能赢得比赛。

•[+ (that)] It is virtually certain (that) she will win the gold medal.几乎可以肯定她会赢得金牌。

•Even if a ceasefire can be agreed, how can they make certain (that) neither side breaks it?即使双方都同意停火，他们又怎么能确保对方不会出尔反尔呢？

•Cancer sufferers no longer face certain death as they once did.癌症患者不再像从前那样面临着必死的命运了。

•This scandal will mean certain defeat for the party in the election.这桩丑闻将意味着该党在选举中必败无疑。

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•I had lunch today with a certain George Michael - not the George Michael, I should explain.我今天和一位叫乔治‧麦可的人共进了午餐——我必须说明一下，不是那个乔治‧麦可。

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•I like modern art to a certain extent/degree , but I don't like the really experimental stuff.在一定程度上我还是喜欢现代艺术的，可是不喜欢太实验性的东西。

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•We have certain reasons for our decision, which have to remain confidential.我们作出这样的决定是有一定原因的，这些原因仍需保密。

•Do you think war is justifiable in certain circumstances?你是否认为在某些情况下战争是正当的？

•The song has a certain appeal, but I'm not sure what it is.这首歌有某种感染力，可是我说不出到底是甚么。

•Certain members of the audience may disagree with what I'm about to say.听众中某些人可能会对我要说的有异议。

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•Certain of the candidates were well below the usual standard, but others were very good indeed.有些候选人与一般的标准相距甚远，但其他一些确实很出色。