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Sit IN vs. Sit ON a Chair 

Sit IN vs. Sit ON a Chair 

English can be tricky. There are plenty of letters in words that don’t need to be there and pronunciation can be less than kind. The grammar of sitting in a chair can be a little complicated at first glance, but once you learn why we use ‘sit in’ and ‘sit on’, using the correct term will be much easier.

The choice in words depends on the type of chair you’re sitting on and if you’re sharing that chair with another person. Let’s break down when to use each phrase and how to determine if you are sitting IN a chair or ON a chair.

Comparing the Words ‘In’ vs ‘On’

Office Girl with many question marks

Looking at the definitions of ‘in’ and ‘on’ will help you determine how you are sitting in a chair.

If something is in something else, it is enclosed or surrounded by it. For example, you are probably reading this in a building. If you are, the walls are probably wrapped around you on all or most sides.

On the other hand, if something is on something else, it is physically touching it and is supported by its surface. There won’t be anything enclosed around the object because it’s not in it, it’s simply on it.

Have a look around and see if you can identify what objects are on pieces of furniture and what items are inside them. This will help you better understand why we sit on some chairs and sit in others.

Sit IN a Chair

Boy relax sitting in an egg chair

If the chair has arms, you are going to sit in it, not on it. You also sit in a wheelchair, or in any other chair that wraps up around you a little.

The best way to understand this is to think of the chair as a box. A box has tall sides, so a person sits inside it. The sides of a box, much like the sides of a chair with arms and a sturdy back, protect you.

If you have an egg chair, for example, you will be sitting in it. In fact, you probably have to put most of your body in the chair to sit in it at all!

However, you can only sit in individual sized chairs. If the chair is large enough for two or more people (making it a couch), you aren’t sitting in it. This is because the chair’s sides are no longer just wrapped around you relatively tightly.

You can also sit in a chair without arms if it’s attached to a desk.

Sitting ON a Chair

Man sitting on chair

Sitting on a chair is exactly like it sounds. You place your body on top of the chair, not settling into it like you would when sitting in a chair.

You normally sit on chairs without any arms. Think of a basic school chair or a dining table chair. There is little support on these chairs, just a back for you to lean back on.

Another good example of something you sit on is a stool. Sitting on a stool is quite simple; you bend down and sit. There are no arms to get in your way, and you can easily get up from a stool just as you would get up from sitting on the ground or on a box.

This is where things may get a little more complicated, especially for non-native English speakers.

Larger chairs, sofas, and benches, regardless of whether they have arms or not, are always sat on not in. This may sound confusing, but there’s a good reason for this.

When you sit in a chair, sofa, or bench with arms, you aren’t being supported by the arms of the piece of furniture–at least not in the way you would be if the chair were smaller. Instead, you are simply sitting on the chair.

A good rule of thumb is to see if anyone else could squeeze into the chair with you. If so, you are probably sitting on it, not in it.

To Sum It All Up

Young people sitting together

You usually sit in a chair with arms, but you will sit on that chair if it’s big enough for two or more people. If a chair is relatively simple and doesn’t have any arms, you will sit on it.

When sitting in a chair, ask yourself how many sides of the chair are supporting you. If it’s just the back of the chair, you are probably sitting on it.

While a chair isn’t a box, it can wrap around you and provide the same sort of safe feeling being put in an enclosed space can. That’s why people love sitting in big and tall armchairs!

English isn’t always straightforward , but determining whether you are sitting in your chair or on your chair can be.