Unicycle, Bicycle, Tricycle, more

I guess you know what a bicycle is.

How many wheels does a bicycle have?

Two, right?

So what would you call the picture on the left?

It doesn't have two wheels, it has three. It is called a tricycle.

Tri- means three. Bi- means two.

Uni- means one.

What do you think something with one wheel would be called?

It is called a unicycle.

Here are more:
Uni= 1- example: uniform. Many students wear uniforms. Everyone wears the same style (one kind) of clothes.
Bi= 2- example: bilingual. Two languages. Someone who speaks two languages is bilingual.
Tri= 3- example: triangle. A shape with three sides.
Quad= 4- example: quadriplegic.
Quint= 5- example: quintuplet. Five babies that are born from the same mother at the same time.
Multi= Many- example: multitalented. Someone who has many talents is multitalented.
There are other words that are similar to these. We will look at those another time.