句型转换。 1. This is my father. (改为一般疑问句) _____ this _____ father? 2. My basketballs are in the box. (改为否定句) My basketballs _____ _____ in the box. 3. Mary's pencil is yellow . (对画线部分提问) _____ _____ is Mary's pencil? 4. I have a big sports collection.(改为一般疑问句) _____ you _____ a big sports collection? 5. This is a ruler. (改为复数句) _____ are _____ .