it 's fun , but it 's a real howler . 
(ROOT (S (S (NP (PRP it)) (VP (VBZ 's) (ADJP (JJ fun)))) (, ,) (CC but) (S (NP (PRP it)) (VP (VBZ 's) (NP (DT a) (JJ real) (NN howler)))) (. .)))
(ROOT (S (S (NP (PRP )) (VP (VBZ ) (ADJP (JJ )))) (, ) (CC ) (S (NP (PRP )) (VP (VBZ ) (NP (DT ) (JJ ) (NN )))) (. )))