(S (S (S (BASENP (DT The) (NNS infections)) (VP (VBP are) (ADJP (RB particularly) (JJ problematic)))) (SBAR (IN because) (S (NP (BASENP (QP (RB nearly) (DT a) (NN quarter))) (PP (IN of) (NP (BASENP (NNS people)) (SBAR (WHNP (WP who)) (S (VP (VBP get) (BASENP (DT a) (NN staph) (NN infection)))))))) (VP (VBP require) (BASENP (NN hospitalization)))))) (PERIOD .))