（）用玫瑰红酸钠试剂检验Ba²⁺时，只有Sr²⁺干扰Ba²⁺的检验。

The winter holiday, when I am looking forward to, is coming. What fun it is to have sports! Play football is one of my hobby. I can also ride my bicycle, climb high mountains, or go skating. Sometime I can play the chess with Grandfather. How interested my holiday will be! But my father is always afraid I would be hurt by a truck, fall into water, and fall off a tree. He is afraid I would fight against others or taken away by bad men.    But if I’m friendly and carefully enough, how will these things happen? I must try best to persuade my father.