Understoke
自下给(燃)料, 底部给煤
🗣️ 情景例句
Yes. I know I must seem silly.
是的，我知道我看来一定很可笑。
I ought to explain to the manager.
我应该向经理解释。
and then there are three thousand million other Milky Ways, or galaxies, in the universe.
况且在宇宙中还有30亿个天河，即银河系。