ultrasonic waves的用法和樣例：
例句
- An instrument that in a painless and noninvasive manner uses the differential transmission and reflection of ultrasonic waves to create a detailed visual image of the brain.
超聲波心動(dòng)描記器一種用來(lái)顯示詳細的大腦圖象的儀器，利用超聲波發(fā)送和反射的差異來(lái)測試并無(wú)傷無(wú)痛
