in four luggage hours , <apostrophe><apostrophe>
(ROOT_0 (S_0 (ATS_2 (PP_2 (IN_0 in) (NP_3 (ATNP_0 (NP_4 (CD_0 four)) (NN_2 luggage)) (NNS_0 hours))) (COMMA_0 ,)) (APOSTROPHE_0 <apostrophe><apostrophe>)))