When to Use Of vs. Off?

• Of is a preposition that indicates relationships between other words, such as belonging, things made of other things, things that contain other things, or a point of reckoning.
• Off is usually used as an adverb or a preposition. In both cases, it indicates separation or disconnection.

---

Mixing them up is always a mistake, but of and off are commonly confused nonetheless. Below, we’ve listed some common situations where you want to use of and some where off is the correct choice.

When to Use Of

We use of when we want to show that people or things relate to other things or people. For example, when we want to say that something or someone belongs to or is a part of something or someone else, we can do it like this:

Tiffany stared at the floor of her room.

He resigned his position as a member of the school board.

We can also use of to say that something consists of something else, or that it contains something else:

He picked up a piece of wood.

She likes to drink a glass of milk before going to bed.

When we want to give a position in space or time, we might use of to link the position with a reference we already know:

He didn’t feel at home north of the Wall.

At the time of the Viking raids, people spoke a very different kind of English.

Of could be used when we create a noun phrase from a verb phrase:

They had to clean up the house before their parents arrived.

They had to clean up the house before the arrival of their parents..

When to Use Off

Off is the opposite of on:

The radio was on, but she needed peace and quiet so she turned it off.

You should always make sure the stove is turned off before leaving the house.

Off can also be used when we want to say that something is away from a place:

He was walking his dog without a leash, and the dog ran off.

After walking Taylor home, Steve set off into the city.

We can use off when we want to say that something has been removed:

He cleaned the spilled soup off the kitchen floor.

They took the wheel off the car.

Examples

My favourite film of 2016 was the spine-tingling British production Under the Shadow from Iran-born, London-based writer/director Babak Anvari.

The Guardian

Can the Guardians battle the bad guys while still keeping their band of ne’er-do-wells together?

Wired

The Briton could only win the title if Rosberg finished off the podium.

Reuters

Sony and its partners showed off a bunch of games at yesterday’s PSX Keynote event.

Forbes