Learn Hardcore Greek: Μιλάς αρκετά καλά ελληνικά τώρα.

μιλάς by itself already means “you speak”.
Saying εσύ μιλάς is possible, but it usually adds emphasis: “you speak (as opposed to someone else)”.

So Μιλάς αρκετά καλά ελληνικά τώρα is the natural, neutral way to say “You speak Greek fairly well now.”

What is the difference between μιλάω and μιλώ? Which one should I use?

They are two forms of the same verb, both fully correct:

μιλάω – slightly more informal / spoken feel
μιλώ – slightly more formal / “literary” feel

In everyday conversation, you will hear both:

Μιλάω ελληνικά.
Μιλώ ελληνικά.

As a learner, you can safely use μιλάω; just be aware you’ll often see μιλώ in writing and in some speakers’ everyday speech.

What tense is μιλάς? Does it mean “you speak” or “you are speaking”?

Μιλάς is present tense (ενεστώτας).

In Greek, the present tense usually covers both:

“You speak Greek (in general).”
“You are speaking Greek (right now).”

Context (and sometimes adverbs like τώρα = now) tells you whether it’s a general ability or something happening at this moment. In this sentence, with τώρα, it feels like “You speak (i.e. can speak) Greek fairly well now”—a general ability at the present time.

Why is it καλά and not καλός in αρκετά καλά ελληνικά?

Καλός is an adjective (“good”) and agrees with a noun:

καλός άνθρωπος – a good man
καλή ιδέα – a good idea
καλό παιδί – a good child

Καλά here is an adverb: “well” (describing how you speak):

Μιλάς καλά. – You speak well.
Τραγουδάς καλά. – You sing well.

So αρκετά καλά means “quite well / fairly well”, modifying the verb μιλάς (“you speak”). That’s why it must be καλά, not καλός.

What does αρκετά mean here? Is it positive or slightly negative?

Αρκετά in this context means “quite / fairly / pretty” (in the sense of degree, not beauty):

αρκετά καλά – quite well / fairly well / pretty well

It is usually positive, but often with a mild, not extreme sense:

Μιλάς αρκετά καλά ελληνικά τώρα.
→ You speak Greek quite well now (better than just “OK”, but not necessarily “perfectly”).

If you wanted something clearly stronger, you might use πολύ καλά = very well.

Why is ελληνικά plural? Why not a singular form for “Greek”?

Language names in Greek are normally neuter plural and without the article when they mean “the language”:

μιλάω ελληνικά – I speak Greek
μιλάω γερμανικά – I speak German
μιλάω ισπανικά – I speak Spanish

Grammatically, ελληνικά is the neuter plural form of the adjective ελληνικός (Greek). Over time, this plural form came to be used on its own as “Greek (the language)”.

You do not usually say μιλάω η ελληνική for “I speak Greek”; that sounds wrong in modern Greek for language ability.

Why is there no article before ελληνικά? Could I say τα ελληνικά?

When you talk about knowing or speaking a language in general, Greek normally drops the article:

μιλάω ελληνικά – I speak Greek
ξέρω ελληνικά – I know Greek

Using the article τα ελληνικά is possible, but then it usually means something more specific or slightly different, e.g.:

Δεν καταλαβαίνω τα ελληνικά σου.
→ I don’t understand your Greek (the way you speak).

In your sentence, Μιλάς αρκετά καλά ελληνικά τώρα, the article-less form is the natural one for “you speak Greek fairly well (as a language)”.

Where can τώρα go in the sentence? Is word order flexible?

Yes, Greek word order is fairly flexible, and τώρα (“now”) can move around:

All of these are acceptable, with slightly different emphasis:

Μιλάς αρκετά καλά ελληνικά τώρα.
Τώρα μιλάς αρκετά καλά ελληνικά.
Μιλάς τώρα αρκετά καλά ελληνικά.

The most neutral versions here are usually:

Μιλάς αρκετά καλά ελληνικά τώρα.
Τώρα μιλάς αρκετά καλά ελληνικά.

Moving τώρα earlier often emphasizes the time: “Now you speak quite well (as opposed to before).”

How do I say the same sentence politely to someone I don’t know well?

Use the formal/plural “you” form of the verb:

Μιλάτε αρκετά καλά ελληνικά τώρα.
→ You (formal / you all) speak Greek quite well now.

The only change is μιλάς → μιλάτε. Everything else stays the same.

What is the difference between μιλάς ελληνικά and λες ελληνικά?

Μιλάς ελληνικά = “You speak Greek” (you can use the language / you’re speaking it).
λες is from λέω = “to say / to tell”.

Λες ελληνικά by itself sounds incomplete or odd; you’d expect an object:

Λες ελληνικά τη φράση λάθος.
→ You say the Greek phrase wrong.

So, for speaking a language, you should use μιλάω / μιλώ:

Μιλάω ελληνικά. – I speak Greek.
Μιλάς ελληνικά. – You speak Greek.

How do you pronounce the words in this sentence, and where is the stress?

Stress in Greek is marked by the written accent (´) on a vowel. In your sentence:

Μιλάς – mi-LÁS (stress on ά)
αρκετά – ar-ke-TÁ (stress on ά)
καλά – ka-LÁ (stress on ά)
ελληνικά – e-li-ni-KÁ (stress on ά)
τώρα – TÓ-ra (stress on ώ)

Each word has only one stressed syllable, and pronouncing the stress correctly is very important in Greek.

How would I make this sentence negative? Where does δεν go?

To make it negative, add δεν right before the verb:

Δεν μιλάς αρκετά καλά ελληνικά τώρα.
→ You don’t speak Greek quite well now.

Pattern: δεν + verb + (other elements)

Δεν μιλάω ελληνικά. – I don’t speak Greek.
Δεν μιλάς ελληνικά. – You don’t speak Greek.