This document discusses the proper use of the prepositions "for" and "since" with the present perfect and past simple tenses. "For" is used with periods of time to indicate how long something has been happening, such as "She lived in Italy for twenty years." "Since" is used to refer to a specific date or point in time to indicate something that began then and continues, like "They have stayed in Italy since September."

1. FOR OR SINCE? Present Perfect and Past Simple

5. THE END