Grammar: preposition: at, on, in

The words at, on and in are preposition of place. Study the following explana

at (very specific) a complete address (with a number) or a spesific location)
on (more specific, a longer area) streets or evenues without numbers, rivers, beaches.
in (a larger area, very general) neighborhood, city, province or country; inside buildings or open areas.
  Azhar : What's wrong with your camera, Tom?