( ( ( Last year ) alone ) ( , ( ( ( nearly ( five million ) ) people ) ( ( enjoyed ( cruise vacations ) ) . ) ) ) )
(ROOT (S (ADVP (NP (JJ Last) (NN year)) (RB alone)) (, ,) (NP (QP (RB nearly) (CD five) (CD million)) (NNS people)) (VP (VBD enjoyed) (NP (NN cruise) (NNS vacations))) (. .)))
Last year alone, nearly five million people enjoyed cruise vacations.
(ROOT (S (NP (QP (RB Nearly) (CD five) (CD million)) (NNS people)) (VP (VBP die) (NP (JJ yearly) (ADJP (JJ due) (PP (TO to) (NP (NN air)))) (NN pollution))) (. .)))