Learn Hardcore Greek: Εσείς μιλάτε ελληνικά πολύ καλά.

You can omit Εσείς. Greek is pro‑drop; the verb ending -τε already shows the subject is “you” plural/formal. Keeping Εσείς adds emphasis (“you in particular”).

Is this addressing one person or several people?

Εσείς/μιλάτε is second‑person plural; it can mean you plural or polite/formal you (singular). Context clarifies which one.

How would I say it informally to one person?

Use second‑person singular: Εσύ μιλάς ελληνικά πολύ καλά, and usually drop the pronoun: Μιλάς ελληνικά πολύ καλά.

What tense and mood is μιλάτε?

Present indicative, 2nd person plural, of μιλάω/μιλώ (to speak).

What’s the difference between μιλάτε and λέτε?

Μιλάτε = you speak (a language). Λέτε = you say/tell. Say “You speak Greek” as Μιλάτε ελληνικά, not Λέτε ελληνικά.

Why is there no article before ελληνικά? Why not τα ελληνικά?

With verbs like speak/learn/know, languages usually appear without the article: μιλάω ελληνικά, μαθαίνω γαλλικά. Use the article when you treat the language as a noun/thing: Τα ελληνικά σας είναι πολύ καλά, Τα ελληνικά είναι δύσκολα.

What exactly is ελληνικά grammatically?

It’s the neuter plural of ελληνικός, used as a noun meaning “Greek (language).” Here it’s the direct object of μιλάτε.

Can I move πολύ καλά to a different position?

Yes. Common options: Μιλάτε πολύ καλά ελληνικά; Πολύ καλά μιλάτε ελληνικά. Word order mostly changes emphasis; all are natural.

Why καλά and not καλός?

Καλά is the adverb “well” (from adjective καλός = good). After a verb you need the adverb: μιλάτε καλά/πολύ καλά, not καλός.

Is πολύ the right form here? I’ve also seen πολλή/πολλοί.

Yes. Πολύ here is an adverb meaning “very” and does not change form. The variable forms πολύς/πολλή/πολύ are adjectives meaning “much/many” (e.g., πολλοί άνθρωποι).

How do I pronounce the sentence?

[eˈsis miˈlate eli.niˈka poˈli kaˈla]. A handy transliteration is: Esís miláte elliniká polí kalá. Stress the syllables with the written accents.

Should ελληνικά be capitalized?

No. Names of languages are lowercase in Greek: ελληνικά, αγγλικά, γαλλικά. It’s capitalized only at the start of a sentence.

Is adding Εσείς a way to be polite?

Politeness comes from using the plural form (μιλάτε) for a single person. Εσείς just emphasizes the subject (“you” specifically). In formal letters you may see capitalized Σας for politeness, but not εσείς in normal prose.

Can I say ομιλείτε ελληνικά instead?

Ομιλείτε is very formal/old‑fashioned. In everyday Modern Greek prefer μιλάτε.

How do I turn it into a question?

Use question intonation and the Greek question mark (;) in writing: Μιλάτε ελληνικά; To ask about proficiency you can say Μιλάτε καλά ελληνικά;

How do I negate it?

Place δεν before the verb: Δεν μιλάτε ελληνικά πολύ καλά. In informal writing you may see δε; the standard form is δεν.

Could I use ελληνική instead of ελληνικά here?

Not by itself. Ελληνική is the feminine singular adjective (e.g., ελληνική γλώσσα = Greek language). As the object of “speak,” use the neuter plural ελληνικά.

Do πολύ and καλά agree with εσείς in any way?

No. They’re adverbs; adverbs don’t agree with the subject. Agreement happens with adjectives and nouns.

Are there more idiomatic compliments I can use?

Yes: Μιλάτε άπταιστα ελληνικά (you speak Greek fluently), Μιλάτε εξαιρετικά/πάρα πολύ καλά ελληνικά (extremely/very very well), or Τα ελληνικά σας είναι πολύ καλά (“Your Greek is very good”).

Can I mix εσύ with μιλάτε (e.g., Εσύ μιλάτε)?

No. Pronoun and verb must match: εσύ μιλάς (singular) vs εσείς μιλάτε (plural/formal).

What are the present‑tense forms of μιλάω/μιλώ?

Both variants are used. Present indicative:

εγώ μιλάω/μιλώ
εσύ μιλάς
αυτός/αυτή/αυτό μιλάει/μιλά
εμείς μιλάμε
εσείς μιλάτε
αυτοί/αυτές/αυτά μιλάνε/μιλούν(ε)

Where are the stress marks and why are they important?

Greek marks one stressed vowel per word of two+ syllables: εσείς, μιλάτε, ελληνικά, πολύ, καλά. Correct stress is essential for natural pronunciation and sometimes for meaning.