Youmaynotpaymuchatte的精选

问题详情：Youmaynotpaymuchattentiontoyourdailyelevatorride.Manyofususealiftseveraltimesduringthedaywithoutreallythinkingaboutit.ButLeeGray,PhD,oftheUniversityofNorthCarolina,US,hasmadeithisbusinesstoexa...