表示不同意<书>no

表示询问<书>or not; used to indicate a question at the end of a sentence

• 不知以为然否？

  I don't know if you agree or not?

• 知其事否？

  Do you know anything about it?

表示不肯定whether or not

• 是否可以？

  Is that OK?

• 是否成功还难说。

  It is still hard to say whether or not it will be successful.

• 你可否派一个人来？

  Can you send someone over?

• 能否帮助，那要看具体条件而定。

  We must first see more specific details before we can decide to help or not.

• 明日能否出发，目前尚未知晓。

  It is still unknown whether or not we can set off tomorrow.

参见：否定[fǒudìng]