( convex ( ( Mirrors ( ( A ( diverging lens ) ) ( is ( mostly concave ) ) ) ) . ) )
(ROOT (S (NP (NN convex)) (VP (VBZ Mirrors) (SBAR (S (NP (DT A) (VBG diverging) (NN lens)) (VP (VBZ is) (ADJP (RB mostly) (JJ concave)))))) (. .)))
convex Mirrors A diverging lens is mostly concave.
(ROOT (S (NP (DT The) (ADJP (RBS most) (JJ common)) (JJ two-lens) (NN telescope)) (, ,) (PP (IN like) (NP (DT the) (JJ simple) (NN microscope))) (, ,) (VP (VBZ uses) (NP (NN convex) (NNS lenses))) (. .)))