1.
a) We've been here FOR an hour.
b) We've been here SINCE 4 o'clock.
2.
a) She hasn't spoken to me FOR 2 weeks.
b) She hasn't spoken to me SINCE last week.
3.
a) They've lived in this street SINCE 1970.
b) They've lived in this street FOR a long time.
4.
a) I haven't had time to do it SINCE last Monday.
b) I haven't had time to do it FOR a few days.
5.
a) We haven't bought a new one SINCE ages.
b) We haven't bought a new one FOR many years.
