Δεν καταλαβαίνω κι εγώ αυτή τη λέξη.

A natural breakdown is:

• Δεν = not / don’t
• καταλαβαίνω = I understand
• κι = and / also here, more like too / also
• εγώ = I
• αυτή = this
• τη λέξη = the word in the object form

So the structure is roughly:

Not understand also I this the word

Of course, in natural English you would say something like I don’t understand this word either or I don’t understand this word either, myself.

Κι is a shortened form of και.

Before a vowel, Greek very often uses κι instead of και, especially in everyday language. Since the next word is εγώ, which begins with a vowel, κι εγώ is very natural.

So:

• και εγώ
• κι εγώ

both mean the same thing, but κι εγώ sounds smoother and is very common.

Here κι εγώ means I too, me too, or also I.

In this sentence, it adds the idea that the speaker is joining someone else in not understanding the word.

So the feeling is:

• I also don’t understand this word
• I don’t understand this word either

It is not just the plain subject I. It is an emphasized I too.

Yes. The ending -ω in καταλαβαίνω already tells you the subject is I.

Greek often drops subject pronouns when they are not needed. But here εγώ is included for emphasis, because the speaker means I too.

Compare:

• Δεν καταλαβαίνω αυτή τη λέξη. = I don’t understand this word.
• Δεν καταλαβαίνω κι εγώ αυτή τη λέξη. = I don’t understand this word either / I too don’t understand this word.

So εγώ is there not because Greek needs it grammatically, but because the speaker wants that extra meaning.

Because λέξη is the object of the verb, so it must be in the accusative case, not the nominative.

• αυτή η λέξη = this word as a subject
• αυτή τη λέξη = this word as an object

Examples:

• Αυτή η λέξη είναι δύσκολη. = This word is difficult.
• Δεν καταλαβαίνω αυτή τη λέξη. = I don’t understand this word.

So in your sentence, λέξη is the thing being understood, so Greek uses the object form: αυτή τη λέξη.

In standard Modern Greek, when a demonstrative like αυτός, αυτή, αυτό comes before a noun, Greek normally also uses the definite article.

So Greek says:

• αυτή η λέξη = this word
• αυτή τη λέξη = this word in the object form

This is normal Greek structure. English does not do this, but Greek usually does.

So αυτή τη λέξη is the standard pattern, not something unusual.

The full form is την, but in spelling it often loses the final -ν before certain consonants.

Since λέξη begins with λ, you normally write:

• τη λέξη

not

• την λέξη

This is very common in Modern Greek. You will see the full -ν kept before vowels and before certain consonants, but not usually before λ.

So here τη λέξη is the normal standard form.

Δεν is the standard negation used before verbs in many basic sentences.

So:

• καταλαβαίνω = I understand
• δεν καταλαβαίνω = I do not understand / I don’t understand

Unlike English, Greek does not need a separate helping verb like do. It simply puts δεν before the verb.

So Greek says:

• Δεν καταλαβαίνω

  literally closer to

• Not I-understand

Greek word order is more flexible than English, but different positions change the emphasis.

Your sentence:

• Δεν καταλαβαίνω κι εγώ αυτή τη λέξη.

highlights the idea that I too am among the people who do not understand it.

You could also hear:

• Κι εγώ δεν καταλαβαίνω αυτή τη λέξη.

This puts stronger focus on κι εγώ right away: I too don’t understand this word.

So the basic meaning stays similar, but the emphasis shifts a little.

That is a very good question.

Very often, if you are responding to someone else’s negative statement, Greek uses ούτε for neither / either.

For example:

• Ούτε κι εγώ καταλαβαίνω αυτή τη λέξη.
• Δεν καταλαβαίνω ούτε κι εγώ αυτή τη λέξη.

These make the either / neither idea more explicit.

Your sentence with κι εγώ is still understandable and can mean I too don’t understand this word, but ούτε κι εγώ is often the more direct match for English me neither / I don’t either.

So:

• κι εγώ = me too / I too
• ούτε κι εγώ = me neither / neither do I

A rough pronunciation guide is:

then ka-ta-la-VE-no kee e-GHO af-TEE tee LEK-see

A few useful notes:

• δ in δεν sounds like th in this
• γ in εγώ is not a hard English g; it is a softer Greek sound
• the stress falls on:
  • καταλαβαίνω
  • εγώ
  • αυτή
  • λέξη

In more phonetic form, it is approximately:

[ðen katalaˈveno ci eˈɣo afˈti ti ˈleksi]