if and only if will be the biconditional statement
im not sure what words should i use but
3 words that i chosen are triangle, square, circle
triangle = 3side figure
square=a rectangle having all four sides of equal length
circle=the portion of a plane bounced by such a curve.
im not sure these are right
and i used these words because i know that biconditional statement is about the geometry
if you have four sides of shape, then its square.
if you have two congruent sides of triangle, then its isosles triangle.
if you have a side but not as the triangle or quare,then its circle.