'Ought' in the Bible

If any man thinketh that he knoweth anything, he knoweth not yet as he ought to know;

or saith he it assuredly for our sake? Yea, for our sake it was written: because he that ploweth ought to plow in hope, and he that thresheth, to thresh in hope of partaking.

For a man indeed ought not to have his head veiled, forasmuch as he is the image and glory of God: but the woman is the glory of the man.

for this cause ought the woman to have a sign of authority on her head, because of the angels.