跑步机level是什么意思

　　例句：

　　The library is all on one level.

　　图书馆全部在同一层楼上。

　　It is important not to let production levels fall.

　　重要的'是别让产量滑落。

　　Water will always find its own level.

　　水总会自行流平。

　　The conflict has now reached a new level of intensity.

　　冲突现在已经达到了新的激烈程度。