1. This is a book. (对画线部分提问) _____ _____ _____? 2. It is an apple. (改为否定句) It ______ _____ an apple. 3. Is it a pen? (改为陈述句) _____ _____ a pen. 4. That's a box. (改为一般疑问句，并作肯定回答) —_____ _____ a box? —_____, _____ _____. 5. I can spell that. (改为一般疑问句) _____ _____ spell that?
