1. This is the classroom in which I met her.
2. This is the playground at/on/in which I met her.
3. This is the coffee shop at/in which I met her.
4. This is the street in/on which I met her.
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Can we use all the prepositions before 'which'? Which ones are incorrect?
1 answer
Yes, all of those prepositions are OK in these sentences. I'd probably omit "in" in sentence 2, but that's a preference, not necessarily incorrect.