Jane: Excuse me, Mary. Is this your backpack? Mary: Oh, no, it isn ’ t. Jane: Is this your backpack, Sonia? Sonia: Yes , it is. Thank you. Jane: What ’ s in your backpack? Sonia: A dictionary, a book and a pencil case. Jane: Yes. What ’ s in the pencil case? Sonia: A ruler, an eraser and a pencil. Jane: Yes. What color is your pencil case? Sonia: It ’ s blue and red. Jane: But this pencil case is yellow. Sonia: Yellow? It ’ s not my pencil case , but this is my backpack. Dale: Hey, this is my pencil case, But this isn ’ t my backpack. Jane: What a mess ( 混乱 ) !