What is the difference between a linking and auxiliary verb?
Linking verbs are limited.
After a verb we generally use an adverb but in linking verb we don't use adverb, instead of using simple adjective.
Like all types of perception or sense verb, like
Feel, appear, sound, smell, become, look, taste seem, etc
It taste nicely==wrong.
We use--it taste nice ( adjective)
Auxiliary verbs are copulative verbs like is/are, was/were etc. that form a verb phrase.
Like I am writing now.
am writing forms a verb phrase. it made it like a sub-verb agreement and here am is functioning like a main verb.
Hope it works.