All but one _____ here just now. [ ] A. 发布时间:2017-07-13 13:45 │ 来源:www.tikuol.com 题型:选择题 问题: All but one _____ here just now. [ ]A. is B. was C. has been D. were
题型:选择题 人体血液的pH为7.35~7.45,其中含有一对物质能抵御外来的少量酸或碱而保持pH基本稳定,这对物质可能是A.NaCl-HClB.NaHCO3-H2CO3C.NaOH-HClD.Na2CO3-HCl 查看答案