Test 13D 阅读理解One of the most important parts of the Deep Time experiment was to study howour brains keep track of time when there are no outside clues,like clocks or themovement of the sun.The campers could sleep and eat whenever they wanted.Overtime,different people developed different schedules(日程安排).Because there wereno clocks,they counted the days according to how many times they slept.深度时间实验最重要的部分之一是研究在没有像钟表或者太阳的移动这种外界线索的情况下，我们的大脑是如何记录时间的。露营者们可以随时随意睡觉和吃饭。随着时间的推移，不同的人制定了不同的日程安排。因为没有时钟，他们根据自己睡觉的次数来计算日子。
