QUESTION: Do for and in mean the same thing when we’re talking about time? My student gave two examples: I haven’t seen him for ages. / I haven’t seen him in ages.
ANSWER: I give preference to in ages, and this is confirmed by at least one dictionary. However, is for ages completely wrong? I don’t think so. If you Google the phrase haven’t for ages, you’ll see a number of ESL/ EFL sites explaining its meaning. Could it be a difference between American English and other Englishes?
With other phrases like for the past hour and in the past hour, the difference is clearer. For is used to express duration and often purpose: She’s been waiting here for the past hour. In is used more to express that something did or didn’t happen within a period: In the past hour he’s called me three times!
Now consider these examples:
- I haven’t exercised in over a week. / I haven’t exercised for over a week.
– Are both correct?
- I didn’t do anything for a long time. BUT I haven’t done anything in a long time.
– If you think both sentences are grammatically correct, does that mean verb tense can dictate which preposition to use?
- I won’t see you for a while. BUT I’ll see you in a while.
– Does for express during that period while in expresses at the end of that period?
Are you yourself stumped?