Grammar · Free lesson
At eight, on Tuesday, in October: choose the time preposition
You are arranging a call. The hour, the day and the month all answer When?, but they do not all take the same English preposition.
Professor Scott MendozaThe short answer
Use at with a clock time: at eight. Use on with a day or date: on Tuesday. Use in with a month or year: in October. Choose by the time expression that follows.
Read the time expression before choosing its preposition.
At points to a clock time. On introduces a day or calendar date. In places the event within a month or year. You can combine two details: The call is on Tuesday at eight. Each preposition belongs to the expression immediately after it.
One call, different levels of detail
The call starts at eight.
The call is on Tuesday.
The next course starts in October.
In the phrase “on Tuesday at eight,” on belongs to Tuesday and at belongs to eight. You do not need to choose one preposition for the entire plan.
Build a plan from two details
Name the day
on Tuesday
Add the clock time
at eight
Put the details together
The call is on Tuesday at eight.
Try it now
Choose the time phrase.
Read all answers and explanations
Complete the plan: “The lesson starts ___ 7:30.”
at7:30 is a clock time, so use at. On fits a day or date; in fits a month or year in these basic patterns.
Complete the sentence: “Our next course begins ___ November.”
inNovember is a month, so use in. Naming the month does not give a specific calendar day.
Keep next and choose the usual complete time phrase.
next TuesdayWe normally use next Tuesday without a preposition. On Tuesday works, but adding next changes this pattern.
Put it into practice
Fix the call invitation.
Keep Tuesday and eight. Correct both time prepositions.
The call is in Tuesday on eight.
See a model answer
The call is on Tuesday at eight.
Choose separately for the day and the hour. Both phrases describe the same call.
A little more clarity
Common questions
A few useful details before you move on.
Why is it on Tuesday morning but in the morning?
The morning is a general part of the day. Tuesday morning names a specific day and part of it, so use on. Let the whole time expression guide your choice.
The class is on Tuesday morning.
What if I give the date instead of the day?
Use on with a calendar date too. Use in when you give only the month or year. This lesson does not cover every holiday or regional expression.
The workshop is on October 14.
Take it into your day
Say at eight, on Tuesday and in October. In a phrase such as next Tuesday, normally leave out the preposition.
Your next step · Available on Udemy
Make your time and place details clearer.
This lesson gives you a small set of time patterns. The English Grammar and English Speaking course includes Prepositions of Time with Learn it, Review it, Use it and Practice it lessons, within a broader grammar and speaking course.
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