I'm not sure whether this really should be called a coma.

我不确定这是否真的该被称作昏迷。

耶鲁公开课 - 死亡课程节选

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

I like to have something that's my own, and continue writing too. I really, I'm not sure.

我想有点自己的东西，还想继续写作。我真的不确定。

为我的生活 - SpeakingMax英语口语达人

I'm just not sure that they really need all of that.

我只是不确定他们是否真的需要那样做。

纽约的交通手段 - SpeakingMax英语口语达人