does so without compromising that complexity 
(ROOT (VP (VBZ does) (ADVP (RB so)) (PP (IN without) (S (VP (VBG compromising) (NP (DT that) (NN complexity)))))))
(ROOT (VP (VBZ ) (ADVP (RB )) (PP (IN ) (S (VP (VBG ) (NP (DT ) (NN )))))))