建立了砂轮的球基渐开螺旋面方程和分度球面螺旋线方程,给出螺旋运动参数、螺旋线导程.The mechanism of grinding internal gear of spherical worm emery - wheel is researched.正圆锥螺旋面是正圆柱螺旋面被同轴正圆锥面截得.The ortho cone helicoid was used interrsect intercept by the ortho con...
The floodwaters have now receded.洪水现已消退。The high water receded.高水位退去了。The clamor of traffic has receded to a distant murmur.车辆的喧闹声已渐渐远去，变得模糊起来。His hairline had receded slightly over the years.这些年来他的前额已经有点秃了。A year on, th...
preconceived opinions.预先的观点Before I started the job, I had no preconceived notions of what it would be like.开始做这工作之前，我并未预想过它的实际情况。Like most 'peacetime wars' it did not conform to preconceived ideas.如同大多数“和平时代的战...
She spent seven days afloat on a raft.她在一只木筏上漂泊了七天。His business is facing difficulties, but it is staying afloat.他的生意遇到一些困难，但还能维持。We kept her afloat for a couple of hours by bailing frantically.我们拼命往外舀水，使它继续漂浮了几个小时。A num...