Question

What is a square a parallelogram but a parallelogram not a square a square

Answer 1

Square is 90 degrees but parallelogram is not

Answer 2

A square has both parallel sides
being the top and bottom
but also both the sides 

AND so does a PARALLELogram
BUT a square has ALL right (90 d) angles 
and a parallelogram does NOT 

ALSO . . . . . SUMMARY . . . . .  
The sides of a square are parallel
and all the angles equal 360 degrees,
so it's a parallelogram. BUT a
parallelogram is NOT a square
because a squares angles need to be 90 degrees.

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