, in a back nap , <apostrophe><apostrophe> <apostrophe><apostrophe>
(ROOT_0 (S_0 (ATS_2 (ATS_0 (ATS_0 (COMMA_0 ,) (PP_2 (IN_0 in) (NP_6 (ATNP_1 (DT_0 a) (JJ_1 back)) (NN_1 nap)))) (COMMA_0 ,)) (APOSTROPHE_0 <apostrophe><apostrophe>)) (APOSTROPHE_0 <apostrophe><apostrophe>)))