W：我想我可以试一下，但不知道会不会奏效。

W: I guess I could try that. But I doubt it will help.

youdao

但我又怎么能为那些我不知道会不会出现的东西感恩呢？

But how then can I be truly grateful for something I know is not there?

youdao

足球让我改变了很多，但我不知道会不会坚持到下一届世界杯。

Football has changed a lot for me and I don't know if I will even make it to the next World Cup.

youdao

Is art important enough to you that you'd be prepared to watch, look at a masterpiece, if you knew that while you were enjoying it you could die, ? but that wouldn't happen otherwise?

艺术有没有重要到,让你准备好去看，去欣赏一件杰作，如果你知道在欣赏它的时候可能会死，但如果不去欣赏就不会死？

耶鲁公开课 - 死亡课程节选

I'm not sure that McCain would have been a whole lot better,

我不知道要是麦凯恩当选了会不会好一点，

担忧未来 - SpeakingMax英语口语达人