题型:判断题 When ________ what his problem was, the boy lowered his head and kept silent.[ ]A. asking B. askedC. having asked D. having been asked 查看答案
题型:判断题 运动时为了预防在运动中脱水,需要()A.在运动中大量多次地补充水分B.在运动开始前喝水300~500mlC.在运动开始前一次性补足水分D.在运动后一次性补足水分E.在运动前、中、后补充大量的白开水 查看答案