at, in, on

We use:

atinon PRECISE TIME MONTHS, YEARS, CENTURIES and LONG PERIODS DAYS and DATES at 3 o'clockin Mayon Sunday at 10.30amin summeron Tuesdays at noonin the summeron 6 March at dinnertimein 1990on 25 Dec at bedtimein the 1990son Christmas Day at sunrisein the next centuryon Independence Day at sunsetin the Ice Ageon my birthday at the momentin the past/futureon New Year's Eve

ExpressionExample at nightThe stars shine at night. at the weekendI don't usually work at the weekend. at Christmas/EasterI stay with my family at Christmas. at the same time We finished the test at the same time. at presentHe's not home at present. Try later.

inon in the morningon Tuesday morning in the morningson 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. (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)

afterlater than…after school ago how far something happened (in the past) 6 years ago beforeearlier than…before Christmas between time that separates two points between Monday and Friday by not later than a special time by Thursday during through the whole of a period of time during the holidays forperiod of timefor three weeks from... to from... till/until two points form a period from Monday to Wednesday from Monday till Wednesday from Monday until Wednesday pasttime of the day23 minutes past 6 (6:23) sincepoint of timesince Monday till/untilno later than a special time till tomorrow until tomorrow totime of the day23 minutes to 6 (5:37) up to not more than a special time up to 6 hours a day withinduring a period of timewithin a day