We use at with times:

at 5 o’clock – at 11.45 – at midnight – at lunchtime

at night – at Christmas – at the moment / at present – at the same time – at weekends – at the age of…


We use on with dates and days:

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 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.


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.


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.


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.


We use until/till to say how long a situation continues:

Let’s wait until it stops raining.

I stayed in bed until half past nine.


We use from – to + beginning and end of a period:

Last evening we watched TV from 5 to 8 o’ clock.