1.lift off (火箭等)發射;(直升飛機)起飛
They are watching spaceship lift off quietly.
他們靜靜地看著宇宙飛船起飛
2.hit the ground 著陸
I felt the shock as the aircraft hit the ground.
飛機著陸時我感覺到了震動
3.prototype 原型
This simple device is the prototype of the commercial alternating current generator, or alternator.
這個簡單裝置就是商用交流發電機的原型
4.bread and butter (某人或公司的)主要收入來源
Out-of-state visitors are our bread and butter.
外省游客是我們的主要經濟來源