On is used for position on a surface.
- There is a big spider on the ceiling.
- The cat is on the roof.
- That picture would look better on the other wall.
On can mean attached to.
- Why do you wear that ring on your first finger?
- There aren’t many apples on the tree this year.
On is also used to talk about position on a line (for example a road or a river).
- Stratford is on the river Avon.
We use on to talk about travel using buses, planes and trains, as well as motor cycles and horses.
- He is arriving on the 3.15 train.
- There is no room on the bus; let’s get off again.
We use on for the number of the floor.
- She lives in a flat on the third floor.
We use on with days.
- I will ring you on Monday.
- My birthday is on May 21st.
- We met on a cold afternoon in early spring.
We use on to talk about one day of the holiday.
- They are having a party on Christmas Day.
- What are you doing on Easter Monday?