this group was colder , <apostrophe><apostrophe>
(ROOT_0 (S_0 (ATS_2 (SBAR_0 (S_1 (NP_0 (DT_1 this) (NN_2 group)) (VP_5 (VBD_1 was) (ADJP_0 (JJR_0 colder))))) (COMMA_0 ,)) (APOSTROPHE_0 <apostrophe><apostrophe>)))