to be certain

基本解释

Whatever you think you know to be certain is probably a lot more flexible than you think.
你经过思考而得到的结论，切忌那么的肯定，任何事情都比你想象的更有弹性。
I knew enough of your disposition to be certain that, had you been absolutely, irrevocably decided against me, you would have acknowledged it to Lady Catherine, frankly and openly.
我完全了解你的脾气，我想，假若你当真恨我入骨，再也没有挽回的余地，那你一定会在咖苔琳夫人面前照直招认出来。
In the absence of good scientific trials, it is impossible to be certain which is which.
在缺乏良好的科学试验的情况下，是不可能确定哪些有效哪些无效的。

"When I was reared in the British West Indies my grandmother used to always tell me, you may not be loved by certain forces in a society and you have to understand why.
Some of the important figures-- there had to be certain inventions to make it work.
一些重要人物以及,重要的创新推动了保险的发展
耶鲁公开课 - 金融市场课程节选
but you've got to be certain when you get out there. And make a positive move.
但是你在外面，你必须要小心。然后积极行动。
我使用自行车 - SpeakingMax英语口语达人

Some doctors may want extra studies to be certain the anti-flushing drug is safe.
FORBES: Merck Stands Tall