在英国杜鹃鸟是报春的使者.In England the cuckoo is the herald of spring.杜鹃鸟预告春天的来临.The cuckoo is the herald of spring.在英国杜鹃鸟预示春天的来临.In England the cuckoo is the herald of Spring....
用阿基米德螺线能成功地解决化圆为方的问题,方法很简单.A neat solution of the quadrature problem can be achieved with the spiral of Archimedes.现在的密封槽型比较常用的是对数螺线槽.Now the commonly used seal groove is a logarithm spiral groove.螺线齿轮被用于传送在平行的轴之间的行动.Hel...