Learn prepositions as part of a system. In identifying the location of a place or an event, the three prepositions at, in, and on can be used. At specifies the exact point in space or time; in is required for expanses of space or time within which a place is located or an event takes place; and on must be used with the names of streets (but not exact addresses) and with days of the week or month.
| AT | There will be a meeting tomorrow at 9:30 am at 160 Main Street. |
| IN | I arrived in the United States in January. |
| ON | The airline’s office is on Fifth Avenue. |
| I’ll be moving to my new apartment on September 30. |