1. They are playing in the room.
2. They are playing at the room.
3. He has just arrived in the room.
4. He has just arrived at the room.
5. The thief found nothing at/in the room, so he left the room and started searching for the living room.
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Do we have to use 'in' before 'room'? What about 'at' in the sentences?
1 answer
1 and 4 are correct. 5 should be in. Think of in as within.