I can see that a set of inflections from a lexeme influence/are influenced by the internal structure/syntax of the sentence (for identification purposes) and form a syntactic class.
I can also see that the pairs "wind" and "unwind" or "large" and "enlarge" are separate lexemes because "un-" and "en-" prefixation do not form a syntactic class of their own. Also, there is no syntactic rule dictating that "un-" or "en-" prefixation must take place in certain internal structures. Rather, the difference is one of semantics not syntax.
Also, inflections of a lexeme do not all have to belong to the same part of speech; however, specifically with verbs, they always do.
Is that all there is to it? I hope somebody can help me with this.

