be sure of

基本解釋

We have to be sure of that first.
我們得確信這是第一位的。
“You can be sure of one thing: I’m leaving,” he says, adding that he has no plans to run for election in 2014.
“有一件事是肯定的：我要離開了，”他說道，同時(shí)還表示他并沒有計(jì)劃參加2014年的競選。
All they can be sure of is that colleges will accept or reject them, and it's like being accepted or rejected for a date—only much more intense, and their parents know all the details.
他們惟一確信的，就是大學(xué)可能接受也可能拒絕他們，就像約會可能被接受或拒絕一樣——只不過前者更嚴(yán)重一些，而且父母會知道有關(guān)的一切細(xì)節(jié)。
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He could not be sure of their support if he declared that the purpose of the war was to free the slaves.
So, he started asking himself the question, "What can I be sure of?"
他首先問自己一個(gè)問題,"我究竟能夠確信什么呢"
耶魯公開課 - 心理學(xué)導(dǎo)論課程節(jié)選
But I'm sure you can easily see how these styrofoam balls could, in fact, be a mono layer of gold nuclei.
這個(gè)實(shí)驗(yàn)怎么工作的,我們先來做些計(jì)算，但我相信你們都已經(jīng)。
麻省理工公開課 - 化學(xué)原理課程節(jié)選

Although now plainly well placed to win the presidency, the Colonel cannot be sure of it.
ECONOMIST: The colonel rides on