あなたの意見はまったく根拠がない。

you (referring to someone of equal or lower status); dear (what a wife calls a husband)

indicates possessive; nominalizes verbs and adjectives; substitutes for "ga" in subordinate phrases; (at sentence-end, falling tone) indicates a confident conclusion; (at sentence-end) indicates emotional emphasis; (at sentence-end, rising tone) indicates question

opinion; view; comment

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

really; truly; entirely; completely; wholly; perfectly; indeed; good grief (expression of exasperation)

basis; foundation

indicates sentence subject (occasionally object); indicates possessive (esp. in literary expressions); but; however; still; and

nonexistent; not being (there); unpossessed; unowned; not had; unique; indicates negation, inexperience, unnecessariness or impossibility; not ...; to not be...; to have not ...