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(ROOT_0 (S_0 (ATS_3 (NP_1 (PRP_0 He)) (VP_4 (ATVP_4 (ATVP_3 (VB_0 be) (PRT_0 (RP_0 up))) (NP_4 (ATNP_0 (NP_6 (DT_0 a) (NNS_1 potatoes)) (COMMA_0 ,)) (POS_0 <apostrophe>s))) (ADVP_0 (IN_2 while)))) (DOT_0 .)))