King George International College Blog

Preposition Help: In, On and At

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Hi there, my name is Rebecca MacNeil and I am an ESL Instructor at KGIC Halifax Campus. Today I would like to talk about a grammar topic that is often confusing for students: PREPOSITIONS.

Prepositions are funny little words in that they don’t look like they would be important, but they are! We use prepositions in English to help us talk about:

1. Time

2. Place

3. Methods

4. Purposes or Reasons

There are a lot of prepositions, and most can be placed into categories:

1. Prepositions of Time

2. Prepositions of Place

3. Prepositions of Purpose

This works fairly well, except for the cases in which we use the same prepositions to express different things. This is what I want to focus on today. There are three tiny prepositions that I feel most ESL students have or will have trouble with at some point…. in, on, and at.

When we talk about in, on, and at, we should always be specific about how they are going to be used. The two most common uses are: as a preposition of time or as a preposition of place. There are very distinct differences about when we should use them. Let’s take a look at prepositions of time first.

As prepositions of time, here are some general rules for in, on, and at.

Preposition Use with…
In Seasons, years, months, minutes, seconds
On Days of the week, holidays, weekend, exact dates
At Exact times, holiday time

Some examples:

  • She had her baby in March.
  • I was born in 1986.
  • My brother came home on Halloween.
  • At 7:00, we have to leave the school.
  • She went back to Iran at Christmas.*

The last example is a little confusing, but this is an example of Christmas as a holiday time, not as in the specific holiday December 25th. This is fairly common in Canada, because there is often a break from work or school between Christmas and the New Year (Yes, at KGIC too!). Another example of a holiday time would be Easter, which is usually celebrated over 4 days even if Easter is technically only Sunday (this year it’s on April 20).

Let’s look at in, on, and at as prepositions of place.

Preposition Use with….
In Things with borders/edges/walls.
On Things that are connected/touching
At General/unspecific locations

Some examples:

  • I am living in Canada.
  • She fell in the pool.
  • The clock is on the wall.
  • Can you hand me the book on the table?
  • I am at the library.
  • Shelly is at the park.

Prepositions of place are a little bit harder for students since the uses are often interchangeable depending on the context. You could be both at the library (an unspecified location in, outside or even near the library) and in the library (within the walls of the building.)  You could be in a boat or on a boat depending on how tall the boat is in relation to the ground. Remember, if you step down, use in. If you step up, use on! To be honest, in many cases, one or more options could be right- make sure you check with your teacher!

That’s all for today! Thanks for reading and I hope you find prepositions a little easier, if not more interesting than before!