去年冬季至今春季，福建多地出现旱情，这时人们急切盼望的天气是（　　）

    I have1good friend and his name is Jack. Here are his2about his life in twenty years. Jack will be a policeman in twenty years because he thinks it's an exciting job. He will live and work3Beijing, because it's a very beautiful city and he likes it very much. He4taller and stronger and he will have short straight hair. In his free time, he will play5sports to6. He will play tennis every day and he will go swimming and skating on weekends. He will7smart clothes like uniform. Jack will have a happy family. Maybe he will have two8. They will be lovely and cute and he will love them very much. Now he9and tries his best10his predictions come true.

在探究平面镜成像时，我们用一根未点燃的蜡烛来代替点燃的蜡烛在镜中的像，以确定像的位置，这种物理方法叫做  （  ）