1. We clean our classroom every day.
    Our classroom ________ ________ every day.
2. They produce silk in Suzhou.
    Silk ________ ________ in Suzhou.
3. They speak English in class.
    English ________ ________ ________ ________ in class.
4. He teaches us ten words every class.
    Ten words ________ ________ to us ________ ________ every class.
5. We use keys for opening the door.
    Keys ________ ________ ________ opening the door.