题目

—Anything more about the Anna's family life? —Well, she makes ______ a rule to go shopping once a week． A．this               B．that              C．herself            D．it 答案：D下列各组物质，前者是混合物，后者是纯净物的是A．淀粉与氯化氢B．钢与浓硫酸C．纯碱与汽油D．胆矾与液氯