Question

1. That is the place in which we can play.

2. That is the place on which we can play.

3. That is the place at which we can play.

4. That is the place where we can play.
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Which preposition do we have to use, at, on, or in? Are they all possible?

Answer 1

All those prepositions will work, depending on what the reference is: on a field, in a gymnasium, at the ballpark.

Sentence 4 is the best!

Answer 2

Sentence 4 is more suitable than others