Are you sure about that?

这事你肯定吗？

《牛津词典》

You are going to get much exercise. Are you sure about that?

你会受到很多训练的。你确定吗？

youdao

Are you sure about that coffee?

你确定不要咖啡吗？

youdao

OK, important -- if you are part of this group here think about it and make sure you understand that.

好的，这很重要，如果刚才你选了可逆过程,请好好想想并且保证已经理解了这个问题。

麻省理工公开课 - 热力学与动力学课程节选

They are about making sure that you get the police, probation, health, social services, to work together.

BBC: News Online

You can be sure that venture investors are being extra careful about who they back with their new funds.

FORBES: China deals, funds still strong despite new reality: ask Ushi, NLVC

If you go down that path, make sure you are thinking about some of the implications.

FORBES: Raising Money From Friends and Family