If the pressure is too low, the heating system will act up.如果压力太低, 供暖系统就会出毛病.The children always act up when their mother is out.母亲不在家,孩子们总是调皮捣蛋.The young herdsman briskly mounted a horse that was inclined to act up with...

act up的音标：act up的英式发音音标为：[ækt ʌp]act up的美式发音音标为：[ækt ʌp]...

（病痛等）复发，炫耀，行动倔强，（机器等）功能失常...