( ( See ( ( ( Convex , ) and ) Lens ) ) . )
(ROOT (S (VP (VB See) (NP (NP (NNP Convex)) (, ,) (CC and) (NP (NNP Lens)))) (. .)))
See Convex , and Lens .
(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)))) (. .)))