读短文，判断正(T)误(F)。 Becky is a little girl. She is only five. She does not go to school and of course, she can't read or write. But her sister Mary is a schoolgirl. She is ten. One day, Mary sees her little sister at the table with a pen in her hand and a big piece of paper in front of her. ' What are you doing, Becky? ' she says. ' I'm writing a letter to my best friend Sally.' says Becky. ' But how can you? ' says her sister. ' You can't write.' ' Well,' says Becky, ' It doesn't matter (没关系), because Sally doesn't know how to read.' (     ) 1. Becky goes to school every day. (     ) 2. Mary can read and write. (     ) 3. Sally can read Becky's letter. (     ) 4. Sally is a friend of Becky's. (     ) 5. Sally is a schoolgirl.