Here are the correct matches based on the definitions provided:
- names a person, place, thing - noun
- stands for a noun - pronoun
- expresses action or state of being - verb
- modifies a noun - adjective
- modifies a verb, adjective, or adverb - adverb
- one who studies languages - linguist
- Hellenic - Greek
- exchange of ideas - communication
- ancestor of English - West Germanic
- important communication tool of man - language
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