あなたの左目は充血していますよ。

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

left eye

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

congestion (with blood); hyperemia; hyperaemia

indicates certainty, emphasis, contempt, request, etc.; used when calling out to someone; used to catch one's breath or get someone's attention; yo!