en_tn/mrk/04/27.md

He sleeps at night and gets up by day

This is something that the man habitually does. AT: "He sleeps each night and gets up each day" or "He sleeps each night and gets up the next day"

gets up by day

"is up during the day" or "is active during the day"

though he does not know how

"though the man does not know how the seed sprouts and grows"