Look, this is my good friend ,I go to school with her. She has a pretty face. On her face, we can see Mickey Mouse and Donald Duck. They are in many nice colours. I like her very much. When I have my lessons, I open her. When I finish(完成)my homework, I close her, There’re many little friends in her body: a ruler, an eraser and some pencils. Now, can you guess what she is ?