题目

阅读下面短文，在空白处填入1个适当的单词或括号内单词的正确形式。 Add oil, a popular Chinese phrasecommonly used to express(encourage),or support, has reportedly been included in the(late) version of the Oxford EnglishDictionary. phrase, 加油 (jia you) in Chinese, literally meansinject petrol to an engine. Chinese often speak it loudlygames and competitions to encourageparticipants. Previously, dozens ofother Chinese phrases have been included in the OED, such as Guanxi —(person)connections that aid business and Lucky Money — cash(give) in red envelopes. In r已知K2O、K2O2、KO2的名称依次是氧化钾、过氧化钾、超氧化钾。那么BaO2的名称是（　　）A．氧化钡B．过氧化钡C．超氧化钡D．无法确定