2D Shapes
It is a 3 sided base shape
Triangle
It is a shape with 1 side
Circle
It is a 4 sided shape
Square
It is a 4 sided shape with 2 short sides and 2 long sides
rectangle
It has 4 sides and can be made with 2 triangles
Diamond
It is a 4 sided shape with no symmetrical sides
Trapezium