No one knows when such a custom first came into existence. 沒(méi)有人知道這種風(fēng)俗什么時(shí)候開(kāi)始有的。
Do you know when this kind of robot came into existence? 你知道這種機器人是什么時(shí)候問(wèn)世的嗎？
The Government had intended to limit the wage increases of all workers to a reasonable amount, but several trade unions got a march on them by receiving very large increases before the new laws came into existence. 政府部門(mén)本來(lái)打算把所有工人的加薪幅度限制在一個(gè)合理的水平上，但是幾個(gè)行業(yè)工會(huì )搶先一步，在新的法規出臺之前就獲得了大幅度的加薪。
