I want to know the answer to the following question:
Whose work habits and environment prevents them from maintaining a regular sleep pattern?
All the background I'm provided with is that "Due to the work nature of airline pilots, who often cross several timezones and regions of sunlight and darkness in one day, and spend many hours awake both day and night, they are often unable to maintain sleep patterns that correspond to the natural human circadian rhythm; this situation can easily lead to fatigue.". Is that enough to answer the question?
Answer: yes