齿轮指形铣刀样板是加工大模数齿轮的主要辅助工具.The finger milling - cutter templet involute gear is the assistant tool mostly to machining big module gear.本文着重阐述了渐开线齿轮齿根过渡曲线的确定以及使用微机设计齿轮指形铣刀样板的方法.It is rapid and accurate in design and drawing ...
一只年轻的海豹在南非干斯拜附近的巨藻丛中觅食.A young fur seal forages amid bull kelp near Gansbaai, South Africa.巨藻的微小部分显示出这种海洋植物非同寻常的特征.A tiny section of kelp exemplifies the extraordinary features of this sea plant....
你要么非常年轻，要么是个不可救药的乐天派。You are either very young or an incurable optimist.乐天派的人a happy-go-lucky sort of person嗜赌的人是死不悔改的乐天派。Gamblers are incorrigible optimists....