请用方框中所给词的适当形式填空，使短文完整正确，（每空只填一个单词，每词只用一次。）

that, boy, box, be, a

Hello. I'm Eric. I'm in my classroom. There are some school things here. Look, this ruler is red. It's Bob's ruler. That's a cup. What color is the cup? It's black. And are my friend Frank's pencils. My pen is black. I can spell it— P-E-N. And there are some pencil on the desk. The pencil boxes red, green and black. I think pencil boxes are black and girls' pencil boxes are red. How about this black one? I know it is not Bill's. Bill says, "My pencil box is brown." Is the green one Tom's? No, it isn't. It's not Tom's. It's Lily's. That pencil box is very beautiful. It is a pencil box with some pictures of birds on it. And there is also English-Chinese dictionary on the desk. Oh, whose dictionary is it?