海词手机词典

In practice ,a rotor weighing about 10 tons Englishand rotating at 3,000 r .p . m . may be so well balanced that the motion ,except for sound ,is just perceptible.

播放读音 播放读音

以上内容独家创作,受著作权保护,侵权必究

海词词典,十七年品牌