Four letter words--Change 0 to 1 letter to make a new word

what?

whet

thow

hats

hats changes 2 letters (in Annie’s own OP)

Working from thow (Scottish variant of thaw)

with

twit

writ

twig

wits

tits

slit

slot

last

late

kale

deal

teal
GO SHARKS!!!

late

bale

bare