Compare at, on, and in:
– They arrived at 5:00.
– They arrived on Friday.
– They arrived in October. / They arrived in 1968.
at for the time of day:
on for days and dates:
on Friday / on Fridays
on May 16, 1999
on Christmas Day
on my birthday
also on the weekend, on weekends
in for longer periods (for example, months/years/seasons):
in the 18th century
in the past
in (the) winter
in the 1990s
in the Middle Ages
in the future
We use at in these expressions:
|at night||I don’t like going out at night.|
|at Christmas||Do you give each other presents at Christmas?|
|at this time / at the moment||Mr. Brown is busy at this time / at the moment.|
|at the same time||Liz and I arrived at the same time.|
in the morning(s) but on Friday morning(s)
in the afternoon(s) on Sunday afternoon(s)
in the evening(s) on Monday evening(s), etc.
- I’ll see you in the morning.
- I’ll see you on Friday morning.
- Do you work in the evenings?
- Do you work on Saturday evenings?
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) and dates (March 12, etc.).
So you can say:
– I’ll see you on Friday. or I’ll see you Friday.
– Seh works on Saturday mornings. or She works Saturday mornings.
– They got married on March 12. or They got married March 12.
In a few minutes / in six months, etc.
– The train will be leaving in a few minutes. (= a few minutes from now)
– Andy has left town. He’ll be back in a week. (= a week from now)
– She’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 learned to drive in four weeks. (= it took me four weeks to learn)