caisson
n
1 large watertight box or chamber in which men can work under water (eg when building foundations) 沉箱(工人进行水下作业, 如建底座时所乘的大潜水箱).
2 large box (usu on wheels) in which ammunition is carried 弹药箱; (通常为)弹药车.
🗣️ 情景例句
You've got lots of time to improve your English.
你已经花了好多时间去提高你的英语水平。
They extended $2.5 million in loans to another country.