(S (S (PP (IN Of) (NP (BASENP (DT those)) (SBAR (WHNP (WP who)) (S (VP (VP (VBD contracted) (BASENP (DT the) (NN virus))) (PP (IN in) (BASENP (NNP Asia)))))))) (COMMA ,) (S (BASENP (NN half)) (VP (VBD died)))) (PERIOD .))