( Fruits ( ( are ( ( composed mainly ) ( of ( ( fructose , ) ( a ( fruit sugar ) ) ) ) ) ) . ) )
(ROOT (S (NP (NNS Fruits)) (VP (VBP are) (VP (VBN composed) (ADVP (RB mainly)) (PP (IN of) (NP (NP (NN fructose)) (, ,) (NP (DT a) (NN fruit) (NN sugar)))))) (. .)))
Fruits are composed mainly of fructose, a fruit sugar.
(ROOT (S (NP (NNP Fructose)) (VP (VBZ is) (NP (NP (DT a) (NN sugar)) (SBAR (WHNP (WDT that)) (S (VP (VBZ is) (VP (VBN found) (PP (IN in) (NP (NNS fruits))))))))) (. .)))