## Shapes

A shape is an external form, boundary, or outline of an object. Different shapes include circles, rectangles, squares, triangles, ovals, stars, diamonds, and pentagons.

~~Circle~~: is a closed two-dimensional figure in which the set of all the points in the plane is equidistant from a given point called “centre”.~~Rectangle~~: is a closed 2-D shape, having 4 sides, 4 corners, and 4 right angles (90°). The opposite sides of a rectangle are equal and parallel.~~Square~~: is a two-dimensional plane figure with four equal sides and all four angles are equal to 90 degrees.~~Triangle~~: is a three-sided polygon that consists of three edges and three vertices.~~Pentagon~~: is a geometrical shape, which has five sides and five angles.**Here, “Penta” denotes five, and “gon” denotes angle.**

## Pen Extension

The pen extension allows sprites to control their pens, as well as stamp themselves onto the stage and remove all pen marks. The pen extension has the following blocks which are of our interest:

~~Pen down~~– The block will make its sprite continuously pen a trail wherever it moves until the Pen Up block is used. The colour, size, and transparency of the trail can be changed with other blocks.

~~Pen up~~– If a sprite is currently using the pen because of the**Pen Down**block, then this block will cause the sprite to stop drawing a trail.

~~Erase all~~– The block removes all marks made by the pen or stamping. It is the only pen block that the Stage can use.