题目

下列反应过程中，同时有离子键、极性键和非极性键的断裂和形成的是（） A . NH4Cl NH3↑＋HCl↑ B . NH3＋CO2＋H2O=NH4HCO3 C . 2Na2O2＋2H2O=4NaOH＋O2↑ D . 2NaOH＋Cl2=NaCl＋NaClO＋H2O 答案：CIf you _____ him yesterday, you _____ what to do now. A．asked … would know           B. had asked … would have known C. asked him … know            D. had asked … would know