1. This is a watch. (变为复数形式)
   __________ are some __________.
2. Can Cindy sing this song in Chinese?(作肯定回答)
   __________, __________ can.
3. This sweater is $28. (对划线部分提问)
    _________ __________ is this sweater?
4. He does his homework in the evening. (改为否定句)
    He __________ __________ his homework in the evening.
5. Tile biology class isn't boring. (改为同一句)
    The biology class __________ __________.