touching or covering a surface
The book is on the table.
held up by something
Hang your coat on the hook.
using a type of transport
We traveled on the bus.
using something
We talked on the phone.
during a day or date
We meet on Fridays.
in a certain state
The TV is on now.
toward something
He smiled on seeing her.
at or near a place
Our house is on Main Street.
because of something
I acted on his suggestion.
right after something
Call me on your return.
about a topic
We had a test on grammar.
supporting a group
Which team are you on?
eating or using regularly
He lives on fast food.
paid by someone
Dinner is on me tonight.
using a phone number
Call me on this number.
affecting someone
Go easy on the salt.
carrying with you
Do you have money on you?
compared to something
Profits are up on last year.
wearing something
What shoes do you have on?
covering something
Put the lid on tightly.
into a vehicle
Get on the bus quickly.
working or operating
Turn the light on.
moving forward
Keep walking on.
continuing
The show goes on.
happening now
The concert is on now.
planned to happen
The meeting is still on.
working or on duty
The doctor is on today.