- at for a PRECISE TIME
- in for MONTHS, YEARS, CENTURIES and LONG PERIODS
- on for DAYS and DATES
MONTHS, YEARS, CENTURIES and LONG PERIODS
DAYS and DATES
|at 3 o'clock
|in the summer
|on 6 March
|on 25 Dec. 2010
|in the 1990s
|on Christmas Day
|in the next century
|on Independence Day
|in the Ice Age
|on my birthday
|at the moment
|in the past/future
|on New Year's Eve
Look at these examples:
- I have a meeting at 9am.
- The shop closes at midnight.
- Jane went home at lunchtime.
- In England, it often snows in December.
- Do you think we will go to Jupiter in the future?
- There should be a lot of progress in the next century.
- Do you work on Mondays?
- Her birthday is on 20 November.
- Where will you be on New Year's Day?
Notice the use of the preposition of time at in the following standard expressions:
|The stars shine at night.
|at the weekend*
|I don't usually work at the weekend.
|I stay with my family at Christmas.
|at the same time
|We finished the test at the same time.
|He's not home at present. Try later.
*Note that in some varieties of English people say "on the weekend" and "on Christmas".
Notice the use of the prepositions of time in and on in these common expressions:
|in the morning
|on Tuesday morning
|in the mornings
|on Saturday mornings
|in the afternoon(s)
|on Sunday afternoon(s)
|in the evening(s)
|on Monday evening(s)
When we say last, next, every, this we do not also use at, in, on.
- I went to London last June. (not in last June)
- He's coming back next Tuesday. (not on next Tuesday)
- I go home every Easter. (not at every Easter)
- We'll call you this evening. (not in this evening)