English prepositions cause a great deal of confusion for non-native speakers. This article is about some of the most common preposition pairs which are easily confused.

In / into

What exactly is the difference between in and into? At least in a few cases, they are both possible. However, there are some differences, too.

Both ‘in’ and ‘into’ refer to three dimensional spaces. In is used to talk about position. Into is used to talk about directions and destinations.

He is not in his office. (NOT He is not into his office.)

She walked into the room. (NOT She walked in the room.)

Into is often used to suggest that people or things move from an outdoor space into an indoor space.

Compare:

She was walking in the garden. (Here in shows position inside the garden.)

Then she walked into her house. (Here into shows movement from the garden to the house.)

She is in her room reading a book.

She ran into the room carrying a paper.

On / onto

The difference between on and onto is similar to the difference between in and into.

On shows position. Onto shows movement or direction.

There is a book on the table. (Position)

He threw the book onto the bed.

The cat is on the roof.

How does it get onto the roof?

Can you get onto the roof without a ladder?

See if you can throw your hat onto the roof.

Into and onto are normally written as single words. On to is also possible in British English.

After some verbs (e.g. throw, jump, push, put) both in and into or on and onto are possible with similar meanings.