derail 就是run off or leave the rails,“出轨,脱轨”的意思,因此我们也可以用run off the rails 来表示列车“出轨,脱轨”,表示某人“出轨”,或者事情“未按计划进行”等意思。如果要表达列车“在轨正常行驶”,事情“正常有序进行”就可以用run on the rails。
来看两个相关例句:
Things are running off the rails recently due to your carelessness.
由于你的粗心,所有的事情近来都乱了套了。
We have made every effort to ensure the ceremony to run on the rails.