( ( The ( convex lens ) ) ( ( magnifies objects ) . ) )
(ROOT (S (NP (DT The) (NN convex) (NN lens)) (VP (VBZ magnifies) (NP (NNS objects))) (. .)))
The convex lens magnifies objects.
(ROOT (S (NP (NP (DT The) (NN lens)) (PP (IN of) (NP (DT the) (NN eye)))) (VP (VBZ is) (S (NP (DT a) (-LRB- -LRB-) (NN n) (-RRB- -RRB-) (NN convex)) (VP (VB shape)))) (. .)))