关于cycle的精选

《cycle of activity》阅读赏析

《cycle of activity》阅读赏析

Weallknowthatthenormalhumandailycycleofactivityisofsome7-8hourssleepalternationwithsome16-17hourswakefulnessandthat,broadlyspeaking,thesleepnormallycoincideswiththehoursofdarkness.Ourpresentconcernisw...