We have just created another chart showing when to use the Prepositions of Time AT, ON and IN.
I hope you find it useful…
UPDATE:
This is the new version created February 2017… (for our video)
You may also be interested in our chart about AT ON IN with Parts of the Day.
See more details about these prepositions including more examples (and exceptions), check out: Prepositions of Time AT, ON and IN
UPDATED 2020:
I have just created these exercises to practice the English prepositions of time AT ON IN: