In, on and at: eight time exercises
Meet at a clock time, on a particular day or in a month. The tricky part is recognising the kind of time expression, not memorising one preposition for everything.
Rules and examples
At: clock times and fixed expressions
Use at with clock times, midday and midnight. At night is a common general expression.
On: days and dates
Use on with a named day, a date or a specified morning or evening.
In: larger periods
Use in with months, years and seasons; also with the morning, afternoon and evening in general.
Sometimes no preposition
Normally omit in/on/at before next, last, every and this in time expressions. For weekends, British English commonly uses at the weekend; American English commonly uses on the weekend.
The gate opens at seven.
The gate opens on Friday.
A clock time takes at. A day takes on.
We patrol in the morning.
We patrol on Monday morning.
A specified morning belongs to a particular day.
A common mistake
Do not say in next Monday. Next already locates the time, so the usual expression is next Monday.
Try the exercises
Choose an answer before opening each explanation. These are self-check exercises, not a CEFR assessment.
Choose in, on, at or Ø. Meet the scout ___ 7:30.
Answer and explanation
at — 7:30 is a clock time.
The market opens ___ Tuesday.
Answer and explanation
on — Tuesday is a named day.
The expedition leaves ___ October.
Answer and explanation
in — October is a month.
The old bridge was built ___ 1998.
Answer and explanation
in — 1998 is a year.
We train ___ the morning, before breakfast.
Answer and explanation
in — The morning is a general part of the day.
We train ___ Friday morning, before breakfast.
Answer and explanation
on — Friday morning is a specified morning.
The creatures usually hunt ___ night.
Answer and explanation
at — At night is the usual expression for nights in general.
The party returns ___ next Monday.
Answer and explanation
Ø — Normally use no preposition before next in a time expression.
Continue in GrammarRift
Crossroads Sewers includes at/on/in for time in its first stage, alongside place prepositions. Later stages cover movement and dependent combinations. The game starts from foundations rather than opening a chosen question directly.
Crossroads Sewers · Stage 1: Foundations
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