That's for sure.

That's for sure
自然是的,必然的,肯定的,正面的,毫无疑问的.
Are you sure (of it)?Are you sure (of it)?
你能肯定吗?你能肯定吗?
Do you feel sure about it?Do you feel sure about it?
你能对这有把握吗?你能对这有把握吗?
I am sure (that) he is right.I am sure (that) he is right.
我肯定他是对的.我肯定他是对的.
Be sure not to forget it.Be sure not to forget it.
千万不要忘记呀.千万不要忘记呀.
Fight no battle you are not sure of winning.Fight no battle you are not sure of winning.
不打把握之仗.不打把握之仗.
I'm not sure whether I've met him before.I'm not sure whether I've met him before.
我不能确定是否以前过他.我不能确定是否以前过他.

就是……当然啦~

That's for sure.
这是毫无疑问的.

那是肯定的

东北话:必须~滴!