Crossing the bar line happens when a sentence like “The rhyme can’t be kept inside” doesn’t end when the bar ends.

当像“The rhyme can't be keep inside”这样的句子在小节结束时没有结束时，就会越过小节线。

They left as soon as Conway had prepared himself for the journey. It was surprisingly simple to leave-a departure rather than an escape; there were no incidents as they crossed the bars of moonlight and shadow in the courtyards.

康威一做好旅行准备，他们就离开了。离开出人意料地简单——离开而不是逃避；他们穿过院子里月光和阴影的栅栏时没有发生任何事件。