as
/əz/
adverb
to the same degree or amount
when considered in a specified form or relation —usually used before a preposition or a participle
as soft as silk
conjunction
as if
in or to the same degree in which —usually used as a correlative after an adjective or adverb modified by adverbial as or so
in the way or manner that
He looks as he had seen a ghost.
pronoun
that, who, which —used after same or such and chiefly dialect after a substantive not modified by same or such
a fact that