for a certainty

基本解釋

And, if we know it for a certainty, how do we know it?
如果我們確實知道這些情況，我們又是如何得知的呢？
I know for a certainty that the company has been bought up.
我確實知道公司已經(jīng)被人收購了。
I was obliged to admit that I did know it for a certainty, and I said to myself, 'Pip, what a fool you are!
可是我又不得不承認(rèn)她一定會帶給我不幸。我在心中暗暗責(zé)備自己：“皮普，你是多么愚蠢??！”

At any rate, I don't know for certainty that I'm a harder grader, but I believe that it's the case based on reactions I get when I give the speech that I'm about to give.
不管怎么，雖然不是特確定我評分嚴(yán)格，但相信應(yīng)該就是這樣,根據(jù)我每次說這些話時得到的反應(yīng)來說。
耶魯公開課 - 死亡課程節(jié)選

Better to wait for a resolution, certainty is better than uncertainty.
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For it is a certainty that no matter what they do, some people will claim that they were too aggressive and others will claim that they were not aggressive enough.
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He has the endorsement of Mr Riordan and of the Los Angeles Times, and his charisma and energy make up for a lack of certainty about how he would run the city.
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