First, the query should look:
(\ b (?! (the | as) \ b) \ w + \ b)
I also added word boundaries to make sure that it matches only whole words, otherwise it will not be able to match the full word “how,” but it will successfully match the letter “s” of that word.
, \w, . , , , , , , \w, . - (Rubular):
/(\b(?!(?:the|as)\b)[a-z'-]+\b)/i
, .