ultrasonic negative-ion generator

例句：

1. 1. Ultrasonic waves are used in medical imaging.
   超声波用于医学成像。
2. 2.The device uses ultrasonic technology to clean the car.
   该设备使用超声波技术来清洁汽车。
3. 3. Ultrasonic cleaners are effective at removing stains from clothes.
   超声波清洁剂能有效去除衣物上的污渍。