Prepositions of Time: A Guide to In, On, and At

“In,” “on,” and “at” are prepositions of time. Each one helps describe time and place. But how do we use them?

If you look at the diagram above, you’ll notice there are some basic guidelines for using “in,” “on,” and “at”.

As we move from “in” to “on” to “at,” we go from a broad, general sense of place or time to a very specific point. Let us explain in more detail below.

1. Preposition “In”

“In” is the most general. We use the preposition “in” when the boundaries are broader and less defined.

For place, we say within a city (“in Paris”) or an object (“in a box”). Typically, we use “in” for something within a larger area or volume.

Similarly, we use the preposition “in” to represent a longer span of time (“in 2020″). It could even mean months, years, centuries, or seasons.

2. Preposition “On”

“On” is more specific than “in” with a more defined time frame. It suggests a clearer, more direct relationship with a location or time.

For location, we use “on” such as being on a street (“on Main Street”). We can also use it to indicate a surface such as “on the table.”

When we use the preposition “on” for time, it’s also more specific. We can use it for days and dates like “on Monday” or “on Christmas Day.”

3. Preposition “At”

The preposition “at” is the most specific. It pinpoints precise locations such as an exact point within a space or time.

For location, it refers to a specific address like (“at 123 Main St.”). It can also define specific locations, such as “at the corner” or “at the door.”

“At” provides the most direct proposition for time too. There’s less ambiguity using it such as “at 3 PM” or “at noon.”