switch on
phrasal verbswitch off/on | switch something off/on
to turn a light, machine, etc. off/on by pressing a button or switch 关／开（电灯、机器等） Please switch the lights off as you leave. 离开的时候请关灯。 How do you switch this thing on? 这东西怎么开？ The electricity has been switched off. 电已经切断了。 We only switched on halfway through the programme. 节目进行到一半时，我们才开始播放。