It depends on...

[FalaGringo]

Does "depends" require a preopisition?

1. It depends on whether he wants to go or not.
2. It depends whether he wants to go or not.
3. It depends on what he wants.
4. It depends what he wants.

 

[emsr2d2]

Does "depends" require a [STRIKE]preopisition[/STRIKE] preposition?

1. It depends on whether he wants to go or not.
2. It depends whether he wants to go or not.
3. It depends on what he wants.
4. It depends what he wants.

All four sentences are possible in BrE. In 1 and 2, "or not" could be omitted.