the subject matter is as adult as you can get 
(ROOT (S (NP (DT the) (NN subject) (NN matter)) (VP (VBZ is) (ADJP (ADJP (RB as) (JJ adult)) (SBAR (IN as) (S (NP (PRP you)) (VP (MD can) (VP (VB get)))))))))
(ROOT (S (NP (DT ) (NN ) (NN )) (VP (VBZ ) (ADJP (ADJP (RB ) (JJ )) (SBAR (IN ) (S (NP (PRP )) (VP (MD ) (VP (VB )))))))))