「しゅんみんあかつきを…なんだっけ…Zzz…」

"In spring, one sleeps like...what was it, again...zzz...." The stock phrase is 春眠暁を覚えず (Shunmin akatsuki wo oboezu, lit. "The sleep of spring knows no dawn"), meaning "In spring, one sleeps like a log", because the temperature is perfect for making one oversleep.