We use FOR to describe the duration of the action
that started in the past and continues into the present.
  • for 5 minutes
  • for 8 hours
  • for 2 days
  • for 4 weeks
  • for 6 months
  • for a few years
  • for a decade
  • for a long time
  • for long
  • for ages
  • for the last two weeks
  • for more than an hour
We use SINCE  to tell when the action started.
  • since 8 o'clock
  • since yesterday
  • since Monday
  • since last week
  • since August
  • since Christmas
  • since 2014
  • since I was 7 (years old)
  • since my birthday (party)
  • since I started learning English
  • since she became a vegetarian
E.g.
Lisa has worked here for 7 years.
David has worked here since 2020.