Wordnet is a database of words: nouns, verbs, adjectives, and so forth linked basically by meaning.
So quite what a simple parser is going to do with it, I don't know.
So I'd wonder why you have to use it?
But...if you must, you must. Start with Google:
WordNet C#[
^] and follow a few links. If they don't solve your immediate problem, then they will likely lead you to a "better search term" which fits your problem.