I'm not sure that your fish will be able to remember what your face looks like, but I wouldn't be too surprised if it could remember you in other ways, perhaps by the sound of your footsteps as you walk towards the tank.

我不确定你的鱼是否能记住你的脸，但如果它能以其他方式记住你，也许是通过你走向鱼缸时的脚步声，我也不会太惊讶。

youdao

I'm not sure what I want to be but I'm sure that you have already known.

我不确定我想成为什么，但我相信你已经知道了。

youdao

I'm not sure that once you reach that point there would be any clear significant advantages to the new designs.

我不能肯定，你一旦达到那个点，将会有非常明确的新设计的明显优势。

youdao

But I'm not sure that you can really make that assumption based on something that someone creates

但我不确定你真的能基于某人创作的某些作品来做那样的推断，

印象深刻的展示会 - SpeakingMax英语口语达人

Now, that is not the most general thing, but I'm sure you guys have some idea of why we are interested in that.

这并不是最普遍的情形,但我确定你们知道我们为什么喜欢它

耶鲁公开课 - 基础物理课程节选

Or you can say "I'm not sure that" when you are uncertain.

或当你没把握时，你可以用 "I'm not sure that"。

I'm sure 课堂 - SpeakingMax英语口语达人

And I think that, you know, I'm not so sure that Reagan would have responded the way you suggest, because some of this democratic progress began under Reagan.

NPR: Role of U.S. Changing in New World Order

I'm not sure you could have said that her freshman and sophomore year.

WSJ: Syracuse falls short against UConn in BEast semis

We just mentioned John Kerry in the intro - I'm not sure you got to hear that part of it.

NPR: Before Midterms, a Chat with Sen. Barack Obama