Learn Hardcore Greek: Σημειώνω κάθε καινούρια λέξη στο τετράδιό μου. - I write down every new word in my notebook.

It usually implies writing something briefly, often as a reminder or record:
- Σημειώνω το τηλέφωνό σου. = I write down your phone number.
Γράφω is more general: “I write” (anything: letters, essays, text, etc.).
- Γράφω μια έκθεση. = I write an essay.

So in this sentence, Σημειώνω κάθε καινούρια λέξη στο τετράδιό μου suggests a habit of jotting down new words in a notebook, not just general writing.

What tense and person is Σημειώνω, and what aspect does it express?

Σημειώνω is:

Present tense
Active voice
1st person singular → “I note down / I am noting down”.

In Greek, the present tense usually combines:

Present continuous meaning: I am writing down (right now)
Habitual meaning: I (always / regularly) write down.

In this context, with κάθε (“every”), it’s clearly habitual:

Σημειώνω κάθε καινούρια λέξη… = I always / usually write down every new word…

Why is it κάθε καινούρια λέξη (singular) and not a plural like “λέξεις”?

Κάθε means “each / every”, and in Greek it is always followed by a singular noun:

κάθε λέξη = each / every word
κάθε μέρα = every day
κάθε άνθρωπος = every person

So:

κάθε καινούρια λέξη = every new word (one by one)

If you wanted to say “all the new words” (plural idea), you would use something like:

Όλες τις καινούριες λέξεις τις σημειώνω στο τετράδιό μου.
= I write down all the new words in my notebook.

What is the form καινούρια here? Why this ending, and what about καινούργια or νέα?

καινούρια here is:

From the adjective καινούριος = new (in the sense of newly acquired, not previously known to me).
Gender: feminine
Number: singular
Case: accusative

It agrees with λέξη (a feminine singular accusative noun):

η καινούρια λέξη (nom.) → την καινούρια λέξη (acc.)
In the sentence: κάθε καινούρια λέξη (accusative as the direct object).

About variants:

καινούρια vs καινούργια: both forms exist in modern Greek; καινούρια (without γ) is more standard, καινούργια is very common in speech. Same meaning.
νέα also means new, but:
- νέος / νέα / νέο is often “young” (a young person) or “new” in a more general / abstract sense.
- καινούριος focuses more on something being newly acquired, newly learned, or unused:
  - νέος νόμος = a new (recent) law
  - καινούριο τετράδιο = a new notebook (one you just bought)
  - καινούρια λέξη = a newly learned word

Why is λέξη in this form? What case is it, and why?

λέξη is:

Nominative singular form: η λέξη = the word
In the sentence, we see λέξη as the direct object, so it is actually accusative singular:
- For this noun, nominative and accusative singular look the same: λέξη.

Declension (basic forms):

η λέξη – the word (nom. sing.)
της λέξης – of the word (gen. sing.)
τη(ν) λέξη – the word (acc. sing.)
οι λέξεις – the words (nom. pl.)
τις λέξεις – the words (acc. pl.)

In Σημειώνω κάθε καινούρια λέξη…, λέξη is the thing being written down, so it’s the direct object → accusative.

What does στο mean, and how is it formed?

στο means “in the / on the / at the” (depending on context).

It’s a contraction of:

σε (in / on / at) + το (the – neuter singular definite article)
→ σε το → στο

So:

στο τετράδιό μου literally = in the notebook my = in my notebook.

Other common contractions:

σε + τον → στον (masculine)
- στον φίλο μου = to / at my friend
σε + την → στη(ν) (feminine)
- στη δουλειά = at work
σε + τους → στους
- στους φίλους μου = to my friends

Why is τετράδιό written with two accents (on ά and ό) in τετράδιό μου?

The base word is τετράδιο (notebook), with the accent on ά:

τε-τρά-δι-ο → τετράδιο

When a word with the stress on the antepenultimate syllable (like τετράδιο) is followed by an enclitic (like μου), Greek spelling rules add a second accent on the last syllable of the main word:

το τετράδιό μου

So in writing you see:

τετράδιό (accents on ά and ό) + μου

This marks that the whole group τετράδιό μου acts as one accentual unit.
In pronunciation, the main stress is still on τρά, with a secondary effect on the last syllable; in everyday speech many people don’t clearly hear the second stress.

In casual writing, some people omit the second accent, but the standard spelling is τετράδιό μου.

What case and form is τετράδιό (μου), and why?

τετράδιο is:

Gender: neuter
Number: singular
Case: accusative

It follows the common neuter pattern:

το τετράδιο – the notebook (nom./acc. sing.)
του τετραδίου – of the notebook (gen. sing.)
τα τετράδια – the notebooks (nom./acc. pl.)

Preposition σε (in/on/at) always takes the accusative, so:

σε + το τετράδιο → στο τετράδιο
With the enclitic: στο τετράδιό μου = in my notebook.

What is μου here, and why does it come after τετράδιό instead of before, like “my notebook”?

μου here is a weak (enclitic) possessive pronoun meaning “my”.

Case: genitive
Person: 1st person singular

Greek normally uses these short forms after the noun:

το τετράδιό μου = my notebook
το βιβλίο σου = your book
το σπίτι του = his house

So the pattern is: [noun + article] + enclitic possessive pronoun.

The full set of weak possessives:

μου – my
σου – your (sing.)
του – his / its
της – her / its
μας – our
σας – your (pl./formal)
τους – their

English uses a possessive before the noun (“my notebook”); Greek usually expresses the same idea with [notebook] + μου: το τετράδιό μου.

Can the word order of the sentence be changed? Are there other natural variants?

Yes, Greek word order is quite flexible. Some natural variants:

Κάθε καινούρια λέξη τη σημειώνω στο τετράδιό μου.
(Adds τη as a pronoun referring back to λέξη, slightly emphasizing each new word.)
Στο τετράδιό μου σημειώνω κάθε καινούρια λέξη.
(Emphasis on in my notebook.)
Κάθε καινούρια λέξη τη σημειώνω στο τετράδιό μου.

The original:

Σημειώνω κάθε καινούρια λέξη στο τετράδιό μου.

is the most neutral, straightforward order: verb – object – prepositional phrase.

How do you pronounce the whole sentence?

Approximate pronunciation with stress in CAPS:

Σημειώνω → si-mi-Ó-no
κάθε → KÁ-the
καινούρια → ke-NÚ-ria
λέξη → LÉ-xi
στο → sto
τετράδιό → te-TRÁ-di-o (with a secondary stress towards the end, due to the extra accent)
μου → mu

Full sentence:

Σημειώνω κάθε καινούρια λέξη στο τετράδιό μου.
→ si-mi-Ó-no KÁ-the ke-NÚ-ria LÉ-xi sto te-TRÁ-di-o mu

Spelling–sound notes:

ει, ι, η, υ, οι often sound like /i/ (like ee in see).
ξ = /ks/ (like x in box).
θ = /th/ as in think, not as in this.