Μην ξεχνάς τον τόνο όταν γράφεις αυτή τη λέξη.

Μην is the negative particle used for commands and instructions. It gives the sense of don’t.

So:

• Μην ξεχνάς = Don’t forget
• Compare with positive:
  • Θυμήσου = Remember
  • Μην ξεχνάς = Don’t forget

In this sentence, μην is what turns the verb into a negative instruction.

It is part of a command.

In Modern Greek, negative commands are usually formed with:

• μην
  • a subjunctive-looking verb form

With many verbs, that form looks exactly like the ordinary present tense form. So ξεχνάς here looks like you forget, but after μην it means don’t forget.

So grammatically, this is not just a plain statement. It functions as a negative command/instruction.

This is a very common question, because both are possible, but they are not identical.

• Μην ξεχνάς uses the imperfective/present stem.
• Μην ξεχάσεις uses the perfective/aorist stem.

The difference is aspect:

• Μην ξεχνάς = Don’t be forgetting / Make sure you don’t forget, often sounding more general, repeated, or ongoing.
• Μην ξεχάσεις = Don’t forget, often referring to one whole event or one specific occasion.

In this sentence, μην ξεχνάς fits a general instruction about spelling the word correctly.

Τον τόνο is the direct object of ξεχνάς.

Breakdown:

• ο τόνος = nominative, the accent / stress
• τον τόνο = accusative, the accent / stress as the object

So:

• ξεχνάς τον τόνο = you forget the accent

The article changes because the noun is the object of the verb.

Here τόνος means the written accent mark.

In everyday Greek, people often say:

• βάζω τόνο = I put the accent
• ξέχασα τον τόνο = I forgot the accent

More generally, τόνος can also mean:

• stress in pronunciation
• tone

But in this sentence, because it talks about writing a word, it clearly means the written accent mark.

Yes, αυτή means this, but in Greek demonstratives are very commonly used together with the definite article.

So Greek normally says:

• αυτή η λέξη = this word in the nominative
• αυτή τη λέξη = this word in the accusative

This is standard Greek structure. English says just this word, but Greek usually uses both the demonstrative and the article.

Both forms exist, but τη is very common before many consonants.

The full article is:

• την

But the final -ν is often dropped before certain consonants in everyday usage, so:

• την λέξη
• τη λέξη

Both can be seen, but αυτή τη λέξη is very natural and standard.

So the sentence is not using a different article; it is just using the shortened form.

Because many feminine nouns in -η have the same form in the singular nominative and accusative.

So:

• η λέξη = nominative
• τη λέξη = accusative

The noun stays λέξη; the article shows the case change.

This is normal for many feminine nouns in Modern Greek.

This is about aspect and time reference.

• όταν γράφεις suggests a general or repeated situation: when/whenever you write
• όταν γράψεις suggests a single future occasion: when you write on one specific occasion

In this sentence, όταν γράφεις αυτή τη λέξη sounds like a general instruction:

• Whenever you write this word, don’t forget the accent

So γράφεις works well because the sentence is giving a general rule.

It is in the accusative singular feminine.

Why?

Because it is the object of γράφεις:

• γράφεις αυτή τη λέξη = you write this word

Breakdown:

• αυτή = feminine singular accusative
• τη = feminine singular accusative article
• λέξη = feminine singular noun

So the whole phrase agrees in gender, number, and case.

A rough pronunciation guide is:

Min kseh-NAS ton TO-no O-tan GRA-fees af-TI ti LE-xi

Main stresses:

• Μην
• ξεχνάς
• τόνο
• όταν
• γράφεις
• αυτή
• λέξη

A few notes:

• χ in ξεχνάς is like the h/ch sound in Scottish loch or German Bach
• γρ in γράφεις is pronounced together at the start of the syllable
• ξ in λέξη sounds like ks

Because τη is an unstressed article, while αυτή is a stressed word.

In Modern Greek:

• Most multisyllable content words have a written accent
• Clitic words like articles often do not

So:

• αυτή gets an accent because the stress falls there
• τη does not, because it is an unstressed article attached closely to the following noun

That is completely normal Greek spelling.