( ( ( The toxicity ) ( of ( vitamin E ) ) ) ( ( is ( very low ) ) . ) )
(ROOT (S (NP (NP (DT The) (NN toxicity)) (PP (IN of) (NP (NN vitamin) (NN E)))) (VP (VBZ is) (ADJP (RB very) (JJ low))) (. .)))
The toxicity of vitamin E is very low.
(ROOT (S (NP (NP (DT The) (JJ main) (NN advantage)) (PP (IN of) (NP (NN urea)))) (VP (VBZ is) (NP (PRP$ its) (ADJP (RB very) (JJ low)) (NN toxicity))) (. .)))