Unit 2 单元测试题. 单项选择(每小题1分， 共15分)从A、B、C、D四个选项中选择可以填入空白处的最佳答案。( )21. Changing schools made a big difference _ his life.A. on B. at C. to D. for( )22. Marys uncle made _ possible for her to travel around the world.A. it B. that C. this D. one( )23. The girl is _, so she needs a guide dog to help her.A. sick B. blind C. tired D. sad( )24. My friend Tom voluntee
