( ( ( A ( complex protist ) ) ( with ( many organelles ) ) ) . )
(ROOT (NP (NP (DT A) (JJ complex) (NN protist)) (PP (IN with) (NP (JJ many) (NNS organelles))) (. .)))
A complex protist with many organelles.
(ROOT (S (NP (JJ Many) (NNS scientists)) (VP (VBP think) (SBAR (S (NP (NNS protists)) (VP (VBP are) (NP (DT the) (JJS oldest) (NNS eukaryotes)))))) (. .)))