I put "He never isn't sleeping" based on what the drop down translations suggested. I'm guessing 'never' here is emphatic, in which case it would be more like "He never, never sleeps!", but I'm not familiar enough with Czech to be sure.
I'm just confused.
Unlike English, using double negative in Czech is usually the proper way to express negation. "On nikdy nespí" simply means "He never sleeps." You cannot say: "On nikdy spí." because it just doesn't make sense.
How would you express a double negative like "he's never not sleeping" in Czech?
A diferent way, nut by a double negative. Nikdy není vzhůru. (vzhůru = not asleep)