control arm的用法和樣例：
例句
- They consist of two switches and a control rod with two moveable collars.
它們包括兩個(gè)開(kāi)關(guān)和一個(gè)帶兩個(gè)活動(dòng)軸環(huán)的操縱桿。 - Studies also show that just like chimpanzees, pigs can also control the joystick in front of a computer screen.
他們在一系列的研究中還發(fā)現，豬能夠像黑猩猩一樣操作計算機屏幕前的操縱桿。
