>>273
Some funnier solutions to the question are as follows.
( 1 ) As a square is categorized into quadrilateral such as parallel tetragon and trapezoid, the following solution holds.
It implies the existence of light source to be able to see four match-sticks.
Then, a match-stick is stood at some angle so as to intersect with one match-stick and make the shadow of the stood match-stick cross another.
( 2 ) Three match-sticks are flicked away from the frame with one match-stick.
So that, the left frame itself becomes a requested square ( or a rectangle ).
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