in each square
( in ( each square ) )
(ROOT (PP (IN in) (NP (DT each) (NN square))))
On the inside of every square except the corners.
( ( On ( ( the inside ) ( of ( ( every square ) ( except ( the corners ) ) ) ) ) ) . )
(ROOT (FRAG (PP (IN On) (NP (NP (DT the) (NN inside)) (PP (IN of) (NP (NP (DT every) (NN square)) (PP (IN except) (NP (DT the) (NNS corners))))))) (. .)))