"Are you sure the raft is safe?" she asked anxiously. "Couldn't be safer," Max assured her confidently.

“你确定这筏子安全吗？”她不安地问。“再安全不过了，”马克斯自信地向她保证。

《柯林斯英汉双解大词典》

Are you sure they'll be the right families?

你确定他们是合适的家庭吗？

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Are you sure you've got that on the right way round ?

你能肯定你没有穿反吗？

《牛津词典》

But if the person who won your heart does not love you, then you are sure to have a broken heart.

VOA: special.2010.07.18

It could also say, what are the methods associated with the string, 1. I'm sure you can quickly graph it, but notice they aren't the same.

我们也可以说，与字符串1相关联的方法有哪些？,我相信你们可以很快的求出来，但是请注意这跟前面的。

麻省理工公开课 - 计算机科学及编程导论课程节选

You just got to be looking around all the time to make sure you are not going to be run down.

你随时观察四周以确保你不会被撞倒。

伦敦的蓝色自行车 - SpeakingMax英语口语达人

Make sure that your policy does not include a clause excluding payment in the event that you are killed in the line of duty, and be sure that you are protected in the event of a traumatic injury.

FORBES: Make a Legal and Financial To-Do List Before Military Deployment

After a certain point you know what you know, you are what you are, and the real purpose is to make sure that you are outstanding at some core strength that you bring to the business.

FORBES: The Three Phases of Careers - Where Are You and Where Should You Be?

During the physical attack there is a person with a knife, and while you may not know his name or see his face, you are 100% sure that the knife you are taking away is in the hands of a bad guy.

CNN: Can you counter-attack hackers?