2021-08-11

first of all,sleeping eight hours a day is a sweet spot? the  one paragraph is quoted a word of famous person.if we spend eight hours a day in our bed means that we spend a third of our in our bed.the second paragraph is used a finding that the amount of sleep you need depends opuntia your age.if you are a adult,you may need more time to sleep, but if you are a infant ,in may need less sleep.there are a group find that  the genes can influence our sleep time.finally,if we actually need certain amount sleep time? The answer is that we must take considerate age into that.