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For and since

351b

For

and since both commonly introduce time expressions which can refer to ‘time up to

now’ and which are used with the present perfect. 

For

refers to periods of time, since refers to a previous point in time:

We

’ve had that TV set for fifteen years.

(We’ve had that TV set since fifteen years.)

I

’ve been awake since half past four this morning.

Expressions with for can also refer to periods of time separated from now, when the period

referred to has come to an end or lies in the past, in which case the past tense is used:

A: I lived in Sweden for five years.

B: When was that?

A: Oh in the 1970s.

✪

Since

is not used with the present simple or progressive when referring to ‘time up to now’:

We

’ve lived/been living in the village since 1987.

(We live/are living in the village since 1987.)