Learn Hardcore Greek: Ντρέπομαι λίγο να μιλήσω ελληνικά μπροστά σε όποιον δεν ξέρω. - I am a bit shy to speak Greek in front of anyone I don't know.

Ντρέπομαι is a so‑called middle/passive verb in Modern Greek. Verbs that describe emotions, feelings, or states (like to be ashamed, to be afraid, to remember) often appear in this form.

ντρέπομαι = I am ashamed / I feel embarrassed
There is no separate object like in English I shame myself; the -μαι form already includes the idea of “myself”.
Active forms like ντροπιάζω = I shame/embarrass (someone else).

So ντρέπομαι is not “I shame myself” literally; it’s just the normal way to say I’m embarrassed.

Is ντρέπομαι here present tense? How would I say it in the past?

Yes, ντρέπομαι is present tense: I am embarrassed / I feel shy (right now, generally).

Basic forms:

Present: ντρέπομαι – I’m embarrassed
Imperfect (continuous past): ντρεπόμουν(α) – I used to be / was embarrassed
Aorist (simple past): ντράπηκα – I got embarrassed (at some point)
Future: θα ντραπώ – I will be embarrassed / I’ll get embarrassed

In a similar sentence in the past, you might say:
Ντράπηκα λίγο να μιλήσω ελληνικά μπροστά σε όποιον δεν ήξερα.
= I was a bit embarrassed to speak Greek in front of anyone I didn’t know.

Why is there no εγώ in the sentence? How do I know it means “I”?

Greek is a pro‑drop language: subject pronouns (εγώ, εσύ, αυτός etc.) are usually left out because the verb ending already tells you the subject.

ντρέπομαι → 1st person singular → I am embarrassed
If you said εγώ ντρέπομαι, that’s correct but more emphatic: I am embarrassed (as opposed to someone else).

So you normally omit εγώ unless you want to stress it.

What exactly does λίγο modify here? Is it “a bit embarrassed” or “speak a bit of Greek”?

In Ντρέπομαι λίγο να μιλήσω ελληνικά…, the default reading is:

ντρέπομαι λίγο = I am a little (bit) embarrassed

So λίγο modifies ντρέπομαι, not μιλήσω.

If you wanted to say to speak a little Greek, you’d change the word order:

Ντρέπομαι να μιλήσω λίγο ελληνικά…
→ now λίγο goes with μιλήσω ελληνικά = to speak a little Greek.

In your sentence as written, it’s about the degree of embarrassment.

Why is it να μιλήσω and not να μιλάω? What’s the difference?

Both are subjunctive forms of μιλάω (to speak), but they differ in aspect:

να μιλήσω – aorist (single event, whole action) → to speak (once/at that time)
να μιλάω – present (ongoing, repeated) → to be speaking / to keep speaking

With ντρέπομαι, Greek strongly prefers the aorist να μιλήσω:

Ντρέπομαι να μιλήσω ελληνικά.
→ I’m embarrassed to (start / do the act of) speaking Greek.

Ντρέπομαι να μιλάω ελληνικά is possible but sounds more like embarrassment about a habitual or ongoing action (e.g. “I’m ashamed to be speaking Greek (all the time)” in some context). For the usual meaning here, να μιλήσω is the natural choice.

Why is ελληνικά in the neuter plural form? Why not something like την ελληνική γλώσσα?

In everyday Greek, languages are almost always used in the neuter plural as adverb‑like objects:

Μιλάω ελληνικά. = I speak Greek.
Μιλάει αγγλικά, γαλλικά και ιταλικά. = He/she speaks English, French and Italian.

You can say μιλάω την ελληνική γλώσσα, but that is formal, heavy, and unusual in casual speech.

So να μιλήσω ελληνικά is the standard, natural way to say to speak Greek.

What does μπροστά σε literally mean, and how is it different from μπροστά από?

μπροστά σε
- noun/pronoun = in front of (someone/something), often with a sense of presence or audience.
μπροστά από
- noun = also in front of, usually more spatial/physical.

In your sentence:

μπροστά σε όποιον δεν ξέρω = in front of anyone I don’t know (as an audience).

Here σε is the natural choice, because you mean “in front of people (as observers)”.
Μπροστά από would focus more on physical position relative to an object:
Μπροστά από το σπίτι = in front of the house.

Why is it όποιον and not something like κάποιον or άνθρωπο που?

The word όποιον here means anyone / whoever in a general, indefinite sense:

μπροστά σε όποιον δεν ξέρω
= in front of whoever I don’t know / anyone I don’t know.

If you said:

μπροστά σε κάποιον που δεν ξέρω
→ in front of someone I don’t know (a single, unspecified person).

Or:

μπροστά σε ανθρώπους που δεν ξέρω
→ in front of people I don’t know (emphasis on people, plural).

So όποιον nicely captures the “any person, whoever it might be” feeling.

Why is όποιον in the accusative case?

Because it’s the object of the preposition σε.

σε + (accusative) is the normal pattern:
σε μένα, σε σένα, σε αυτόν, σε όποιον…

In μπροστά σε όποιον δεν ξέρω:

the preposition is σε
it needs an accusative pronoun → όποιον (masculine singular accusative of όποιος).

Grammatically it’s: μπροστά σε (όποιον), and the clause δεν ξέρω just describes that person.

Why is δεν placed before ξέρω? Could it go somewhere else in that clause?

In Modern Greek, δεν (or δε(ν) in speech) almost always comes immediately before the verb it negates.

In the clause (όποιον) δεν ξέρω:

verb = ξέρω (I know)
negative = δεν ξέρω = I don’t know

You can’t move δεν far from the verb; you would not say όποιον ξέρω δεν or similar. The order όποιον δεν ξέρω is the normal way to say whom I don’t know.

Can I change the word order, for example: Ντρέπομαι να μιλήσω ελληνικά λίγο μπροστά σε όποιον δεν ξέρω? Does it sound natural?

Moving words around is possible in Greek, but it changes emphasis and sometimes clarity.

Ντρέπομαι λίγο να μιλήσω ελληνικά… (original)
→ λίγο clearly goes with ντρέπομαι = I’m a little embarrassed.

If you say:

Ντρέπομαι να μιλήσω ελληνικά λίγο μπροστά σε όποιον δεν ξέρω.

then λίγο is closer to μιλήσω ελληνικά, so it tends to be heard as:

I’m embarrassed to speak a little Greek in front of anyone I don’t know.

That’s a different nuance. For natural, clear Greek:

to mean a bit embarrassed: Ντρέπομαι λίγο να μιλήσω ελληνικά…
to mean speak a little Greek: Ντρέπομαι να μιλήσω λίγο ελληνικά…

Could I express the same idea using αγνώστους instead of όποιον δεν ξέρω?

Yes, that’s possible and quite natural. For example:

Ντρέπομαι λίγο να μιλήσω ελληνικά μπροστά σε αγνώστους.
= I’m a bit embarrassed to speak Greek in front of strangers.

Differences in nuance:

μπροστά σε όποιον δεν ξέρω
→ stresses my personal knowledge: anyone I personally don’t know.
μπροστά σε αγνώστους
→ uses a generic noun strangers; slightly more general/impersonal.

Both are correct; your original sentence is perfectly natural as it is.