ultrasonic

◎ ultrasonic是什么意思 n. 超声波a. 超音速的 s having frequencies above those of audible sound ultrasonic的用法和例句： 1. No, it's ultrasonic, so you wouldn't be able to hear it. 不 它以超声波形式存在 所以你听不到 2. Have him monitor the city for any abn...