1. We had a maths exam yesterday.  (对划线部分提问)
    _____ _____ you _____ yesterday?
2. I want to get another piece of cake.  (保持原意，改写句子)
    I _____ ______ to _____ _____ _____ piece of cake.
3. The snow was very heavy yesterday.  (改为同义句)
    _____ _____ very _____ yesterday.
4. He'll buy some school things tomorrow.  (改为否定句)
    He ______ ______ ______ school things tomorrow.