Milk.
Lost. That is the word that comes to my mind at the moment. Emma
The first one that comes to mind is four; others are:anusaquablueblurboutchugchumclubcluecoupcrudcruxdaubdourdrugdrumfaunfauxfluxfoulglueglumglutgoutgrubhaulhourlaudloudloutmaulnounonusopusovumplugplumpluspoufpourpoutroutscumshunshutslugslumslursmugsmutsnubsnugsoulsoupsourspudtautthudthugthustourtrueyour
bred (As in you have bred the cattle)
Some four letter words with second letter U and fourth letter O are:autoeurojudokudoouzo
Star, stat, stop, stir, and step are some four letter words with the second letter 't'
WIND
Cows do not have two or four stomachs. They only have one stomach with four chambers. Thus, the chambers go as follow, in order from front to rear: reticulum, rumen, omasum, and abomasum.
Some four letter words with a second letter U are:auraburncurbcuredulldumbeurofundguruhugejumpjunklumpluremuchmutenudeoustpullpurepushrulerumpruinruserushrustsuchsurftune
dyes
open
Noel (Christmas) is one holiday with four letters.
Japan