121 : at/on/in (time)

   A   

Compare at, on and in:

• They arrived at 5 o'clock.
• They arrived on Friday.
• They arrived in October. / They arrived in 1998.

 

We use:

 

at for the time of day

    at five o'clock    at 11.45    at midnight    at lunchtime    at sunset    etc.

 

on for days and dates

    on Friday / on Fridays           on 16 May 2009

    on Christmas Day                  on my birthday

 

in for longer periods (for example: months/years/seasons)

    in October                              in (the) winter

    in 1998                                    in the 1990s

    in the 18th century               in the Middle Ages

    in the past                              in (the) future

 

 

   B   

We use at in these expressions:

 

at night	I don't like working at night.
at the weekend / at weekends	Will you be here at the weekend?
at Christmas	Do you give each other presents at Christmas?
at the moment / at present	The manager isn't here at the moment / at present.
at the same time	Kate and I arrived at the same time.

 

 

   C   

We say:

 

    in the morning(s)                  on Friday morning(s)
    in the afternoon(s)     but     on Sunday afternoon(s)
    in the evening(s)                   on Monday evening(s)     etc.

 

• I'll see you in the morning.
• Do you work in the evenings?
• I'll see you on Friday morning.
• Do you work on Saturday evenings?

 

 

   D   

We do not use at/on/in before last/next/this/every:

• I'll see you next Friday. (not on next Friday)
• They got married last March.

 

 

In spoken English we often leave out on before days (Sunday/Monday etc.). So you can say:

• I'll see you on Friday.  or  I'll see you Friday.
• I don't work on Monday mornings.  or  I don't work Monday mornings.

 

 

   E   

In a few minutes / in six months etc.

• The train will be leaving in a few minutes. (= a few minutes from now)
• Andy has gone away. He'll be back in a week. (= a week from now)
• They'll be here in a moment. (= a moment from now)

 

 

You can also say: in six months' time, in a week's time etc.

• They're getting married in six months' time.  or  ... in six months.

 

 

We also use in ... to say how long it takes to do something:

• I learnt to drive in four weeks. (= it took me four weeks to learn)

 

 

 

 (American English -> Appendix 7) 

 

121B

BRITISH at the weekend / at weekends: Will you be here at the weekend?

AMERICAN on the weekend / on weekends: Will you be here on the weekend?