進ㄐㄧㄣˋjìn退ㄊㄨㄟˋtuì有ㄧㄡˇyǒu常ㄔㄤˊcháng

進退都有規律。《四部叢刊本鶡冠子·卷中·泰鴻》：「日信出信入，南北有極，度之稽也；月信死信生，進退有常，數之稽也。」

英to advance or retreat, each has its rules (idiom from Zhuangzi); many translations are possible