Understand the pattern
Prepositions of time: at seven o’clock; on Monday/on 12 May; in June/in 2026/in the morning. Use at night, but in the evening. Place: in a room or area, on a surface/floor, at an exact point such as at the entrance. Meaning decides: at school refers to the school activity/site, while in the classroom places someone inside a room. A visit plan needs both time and meeting point.