( ( Some sources ) ( ( say ( that ( ( ( as ( many ( as nine ) ) ) ( different species ) ) ( are ( visiting ( our planet ) ) ) ) ) ) . ) )
(ROOT (S (NP (DT Some) (NNS sources)) (VP (VBP say) (SBAR (IN that) (S (NP (QP (RB as) (JJ many) (IN as) (CD nine)) (JJ different) (NNS species)) (VP (VBP are) (VP (VBG visiting) (NP (PRP$ our) (NN planet))))))) (. .)))
Some sources say that as many as nine different species are visiting our planet.
(ROOT (S (S (NP (EX There)) (VP (VBP are) (NP (QP (RB about) (CD 50,000)) (JJ vertebrate) (NNS species)))) (, ,) (CC and) (S (NP (PRP they)) (VP (VBP are) (VP (VBN placed) (PP (IN in) (NP (CD nine) (JJ different) (NNS classes)))))) (. .)))