There is a hole in the shaft through which the air from the upper chamber enters the lower one.

 
  • 腔筒中心有一孔道,壓縮空氣就是由此從上氣室進(jìn)入下氣室的。
今日熱詞
目錄 附錄 查詞歷史
国内精品美女A∨在线播放xuan