an eye on preserving a sense of mystery 
(ROOT (NP (NP (DT an) (NN eye)) (PP (IN on) (S (VP (VBG preserving) (NP (NP (DT a) (NN sense)) (PP (IN of) (NP (NN mystery)))))))))
(ROOT (NP (NP (DT ) (NN )) (PP (IN ) (S (VP (VBG ) (NP (NP (DT ) (NN )) (PP (IN ) (NP (NN )))))))))