( Eating ( ( only part ) ( of ( the plant ) ) ) )
(ROOT (NP (NP (NNP Eating)) (NP (NP (JJ only) (NN part)) (PP (IN of) (NP (DT the) (NN plant))))))
Eating only part of the plant
(ROOT (S (NP (DT The) (NN heterotroph)) (VP (VBZ eats) (NP (UCP (ADJP (JJ only)) (CC or) (ADVP (RB mainly))) (NNS plants))) (. .)))