flue block

例句：

1. 1.The engineer installed a new flue block to improve the efficiency of the chimney.
   工程师安装了一个新的烟道挡板，以提高烟囱的效率。
2. 2. The flue block is designed to prevent smoke from entering the room during cooking.
   烟道挡板设计用来防止烹饪时烟雾进入房间。
3. 3. The flue block was removed to inspect the heating system and ensure it was functioning properly.
   移除了烟道挡板以检查供暖系统并确保其正常工作。