A red-eye flight is any flight departing late at night and arriving early the next morning. The term red-eye, common in North America, derives from the fatigue symptom of having red eyes, which can be caused or aggravated by late-night travel. Inside the US these flights almost exclusively travel from the West to the East. These flights are very low cost since significantly less people acquire them due to the inconvenience of touring so late at evening.
紅眼航班是深夜出發(fā)、第二天凌晨抵達的航班，在北美很常見。由于深夜飛行導致兩眼發(fā)紅的疲態(tài)，所以被稱作紅眼。在美國國內(nèi)，紅眼航班基本都是從美西飛到美東。這種航班票價很便宜，因為深夜旅行很不方便，所以很少有人買。
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A red-eye flight is much more economical.
紅眼航班更經(jīng)濟實惠點。
