Underframing
底层框架的材料或结构部件
🗣️ 情景例句
I understand
听说，
Excuse me! I'm sorry I startled you!
对不起！很抱歉，让你受惊了！
They all went up some narrow steps into a large room.
他们全都登上这些狭窄的台阶，接着进入一个大房间。