Prepositions of Time: at, in, onWe use:
•at for a PRECISE TIME
•in for MONTHS, YEARS, CENTURIES and LONG PERIODS
•on for DAYS and DATES
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:
at night
at the weekend
at Christmas/Easter
at the same time
at present
Notice the use of the prepositions of time in and on in these common expressions:
in on
in the morning - on Tuesday morning
in the mornings - on Saturday mornings
in the afternoon(s) - on Sunday afternoons
in the evening(s) - on Monday evening
When we say last, next, every, this we do not also use at, in, on.
•I went to London last June.
•He's coming back next Tuesday.
•I go home every Easter.
•We'll call you this evening.
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