Student or Learner
May I ask a question about "whether"?
The word, whether, is used to indicate choices. I have two simple examples below.
(1) Whether or not you fail, you should try hard.
(2) You need to go to the library earlier whether you get there by bus or by taxi.
Can I use "whether" in the following sentence?
(3) I wonder whether you messed up my table with paint on purpose or you just wanted to demonstrate your artistic skills on it.
I use the same logic here as I did in (1) and (2).
Some people say that "whether" is not correctly used in (3).
Could someone please explain it? Thank you very much.