题目

Every student is asked to come to school ______．A.in time B.for time C.at time D.on time 答案：【答案】D【解析】句意：每个学生被要求按时来学校。本题考查介词短语辨析。A. in time及时；B. for time为了时间；C. at time形式错误，应为at times“有时”；D. on time按时。根据句意可知，表示“按时到校”，故选D。all the time一直、总是at times有时from time to time有时once upon a time从前for the first time第一次at th如图，在四边形ABCD中，AD=BC，点P是对角线的中点，点E和点F分别是CD与AB的中点．若∠PEF=20°，则∠EPF的度数是（　　）A．110°B．120°C．130°D．140°