Sure Why not?

当然，为什么不？

youdao

He prowled around the room, not sure what he was looking for or even why he was there.

他在房间里悄悄地走来走去，不知道自己在找什么，甚至不知道自己为什么在那里。

《柯林斯英汉双解大词典》

Share your thoughts with us! I'm not sure, but why would anyone do so?

和我们分享你的想法吧！我不确定，但为什么会有人这么做呢？

youdao

Sure. Why not? A few of us were leaving.You could take their place.

VOA: standard.other

You feel physiologically aroused but you're not completely sure why, and you have to make up an explanation for it.

你感觉到性觉醒,但是不能确定是什么原因，你不得不给出一个解释。

耶鲁公开课 - 心理学导论课程节选

so this is why I'm not, I'm not a hundred percent sure

所以我也不能确定，

关于宿舍制度 - SpeakingMax英语口语达人

William Greenwood, property manager at Bodnant Garden, said no-one was sure why dogs had not been allowed in until now.

BBC: Bodnant Garden allows in pet dogs for the first time

But Democrats say they will continue this line of debate, and point to Bush's admission at a Monday news conference that even he was still not sure exactly why a required form disclosing a major stock transaction 11 years ago was not filed until eight months after the deadline.

CNN: Bush to propose jail time for corporate misconduct

Number one is a master cleanse, number two is a Ratatouille, which I'm not sure why.

NPR: 'iPhone' Tops Google Zeitgeist List