Prepositions of Time

ON
We use on with dates and days:
on 12 March - on Friday(s) - on Friday morning(s)
on Sunday afternoon(s) - on Saturday night(s)
on Christmas Day (but at Christmas)


AT
We use at with times:
at 5 o’clock - at 11.45 - at midnight - at lunchtime
Tom usually gets up at 7 o’clock.

We use at in these expressions:
at night - at Christmas - at the moment / at present - at the same time - at weekends - at the age of...


IN
We use in for longer periods of time:
in April - in 1986 - in winter - in the 19th century - in the 1970s - in the morning(s) / in the afternoon(s) / in the evening(s)

In + period of time = a time in the future:
Jack will be back in a week.
The train will leave in a few minutes.

In + how long it takes to do something:
I learned to drive in four weeks.


FOR
We use for + a period of time:
for six years - for two hours - for a week
I’ve lived in this house for six years. They have been watching TV for two hours.


DURING
We use during + noun to say when something happens:
during the film - during our holiday - during the night

I fell asleep during the film.
We met a lot of interesting people during our holiday.


SINCE
We use since + a period of time:
since April - since 1992 - since 8 o’ clock
It has been raining since one o’ clock. They’ve known each other since they were at school.