You can't have a one-sided shape, or even a 2 sided shape. If it's a shape, then it needs to:
1) Be made of only straight lines. NO CURVES!
2) Be closed in by the lines. NO OPENINGS!
So I'll start at 3:
3 Sided: Triangle
4 Sided: Quadrilateral
5 Sided: Pentagon
6 Sided: Hexagon
7 Sided: Heptagon
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