Genesis 41:29 Meaning

27And the seven thin and ill favoured kine that came up after them are seven years; and the seven empty ears blasted with the east wind shall be seven years of famine.

28This is the thing which I have spoken unto Pharaoh: What God is about to do he sheweth unto Pharaoh.

29Behold, there come seven years of great plenty throughout all the land of Egypt:

30And there shall arise after them seven years of famine; and all the plenty shall be forgotten in the land of Egypt; and the famine shall consume the land;

31And the plenty shall not be known in the land by reason of that famine following; for it shall be very grievous.