PREPOSITIONS OF TIME

AT	ON
We use at with times:	We use on with dates and days:
at 5 o’clock - at 11.45 - at midnight - at lunchtime	on 12 March - on Friday(s) - on Friday morning(s)
Tom usually gets up at 7 o’clock.	on Sunday afternoon(s) - on Saturday night(s)
	on Christmas Day (but at Christmas)
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	DURING
We use in for longer periods of time:	We use during + noun to say when something happens:
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)	during the film - during our holiday - during the night
In + period of time = a time in the future:	I fell asleep during the film.
Jack will be back in a week.	We met a lot of interesting people during our holiday.
The train will leave in a few minutes.
In + how long it takes to do something:
I learned to drive in four weeks.	www.english-4u.de/prepositionoftime.htm