他的生活每天一成不变,没有任何新意思。Tā de shēnghuǒ měitiān yìchéngbúbiàn, méiyǒu rènhé xīn yìsi.His daily life is unchanging, without anything new.
计划不能一成不变,要根据实际情况做调整。Jìhuà bù néng yìchéngbúbiàn, yào gēnjù shíjí qíngkuàng zuò tiáozhěng.A plan must not stay rigid and unchanging; it has to be adjusted according to the real situation.
爷爷的习惯几十年一成不变,全家人都知道。Yéye de xíguàn jǐshí nián yìchéngbúbiàn, quán jiā rén dōu zhīdào.Grandpa's habits have stayed exactly the same for decades; the whole family knows them.