Prepositions of Place: at, in, on
In general, we use:
• at for a POINT
• in for an ENCLOSED SPACE
• on for a SURFACE
at
POINT in
ENCLOSED SPACE on
SURFACE
at the corner in the garden on the wall
at the bus stop in London on the ceiling
at the ***r in France on the ***r
at the top of the page in a box on the cover
at the end of the road in my pocket on the floor
at the entrance in my wallet on the carpet
at the crossroads in a building on the menu
at the front desk in a car on a page