hydroplane
n
1 light motor boat with a flat bottom, that can travel fast over the surface of the water 机动平底快艇.
2 device on a submarine enabling it to rise or descend (控制潜艇升降的)水平舵.
🗣️ 情景例句
Oh, congratulations! That's nice.
啊, 恭喜你们! 太好了。
I've changed my mind.
我已经改变主意。
for it is then almost ready to undertake heavy work and can begin to earn its keep straight away.