since and for
SINCE points to the BEGINNING of a period of time. SINCE is followed by a specific past time. It usually requires a perfect verb in the main clause:
FOR indicates the LENGTH of a period of time (with no reference to WHERE in time that period is located). FOR is followed by a number or amount of time. The rest of the sentence tells the time, which can be past, present, future, or anything.
choose the right answer
1. ... yesterday
A. ? FOR
B. SINCE
2. ... a long time.
A. FOR
B.
? SINCE
3.
... a few minutes.
A. ? FOR
B. ? SINCE
4.
... last autumn.
A. ? FOR
B. ? SINCE
5.
...
I arrived here.
A. ? FOR
B. ? SINCE
6.
... last night.
A. ? FOR
B. ? SINCE
7.
... two days.
A. ? FOR
B. ? SINCE
8.
... six hours.
A. ? FOR
B. ? SINCE
9.
... 1999.
A. ? FOR
B. ? SINCE
10.
... the Second World War.
A. ? FOR
B. ? SINCE