1. Tell me what you won.

2. Tell me what you won in the competition.
3. Tell me what you won in the race.
4. Tell me what you won in the English speech contest.
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Are they all grammatical?
Is 'what' an interrogative pronoun? Or is 'what' a relative pronoun?

1 answer

All are correct.

In these sentences, "what" is an interrogative pronoun since it introduces an indirect question in each.

What did you win?
What did you win in the competition?
etc.