On-In | Commonly Confused Words

On

/ɒn/

Indicating a position touching or in contact with the surface of a place or object

I think the wallet is on the table.From then on she took control of everything.He turned and put his hand on Silver Blaze is back.

This word has no antonyms

/ɪn/

Used to indicate location or position within something

There's some sugar in the cupboard.In walked the Counsellor, calling out:It is the only way to succeed in in - business.'

Remember on as being more about surfaces and contact, while in involves enclosure or being inside something.
If you think about the phrase on top, it represents being above a surface, whereas in would be embedded within something.
Use on when dealing with something that lies atop a flat or horizontal surface, such as on the table.
When you need to express being contained or surrounded by something, in is your word, like in the box.
On is often used for dates and days, as in on Monday, while in might describe longer periods, like in October.