drowsier
adj. 更困倦的;更沉寂的;更催眠的
例句
If you are getting drowsier on successive days, then you are getting less than your daily requirement and should add 15 to 30 minutes to your sleep time.
如果接连几天都感到瞌睡,那么,你就没有达到每天所需的睡眠量,应该再增加15到30分钟的睡眠时间。