on and off是什么意思

on and off的音标：on and off的英式发音音标为：[ɔn ænd ɔf]on and off的美式发音音标为：[ɑn ənd ɔf]...

Sam was flicking a flashlight on and off.萨姆啪啪不停地把手电筒开了又关。It rained on and off all day.哩哩啦啦下了一天雨.This low-impact exercise involves stepping on and off a platform following routines to music.这一低强度锻炼的内容包括在伴随音乐做完固定动作之后重复踏上踏下...