题目

It is generally considered unwise to give a child        he or she wants.        A．however   B．whatever   C．whichever D．whenever 答案：B下列反应是中和反应的是A.CO2+2NaOH══Na2CO3+H2OB.SO2+2NaOH══Na2CO3+H2OC.NaOH+HCl══NaCl+H2OD.Fe2O3+6HCl══2FeCl3+3H2O