把下列各句改为被动语态。 1. We clean our classroom e
题型：句型转换
问题：
把下列各句改为被动语态。
1. We clean our classroom every day.
Our classroom _____ by us 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.
