例句與造句

1. ultrasonic motors are a new kind of solid actuators that come into being since 1980 ’ s, which use inverse piezoelectric effect of pzt to excite stator ’ s elliptical vibration and produce driving power by frictional coupling
   超聲波馬達是上世紀80年代開始發展起來的一種新型驅動器,它是利用壓電陶瓷的逆壓電效應激勵出定子表面質點的橢圓軌跡振動,依靠摩擦耦合來實現驅動。
2. It's difficult to find frictional couple in a sentence. 用frictional couple造句挺難的