Ο ύπνος με βοηθάει όταν έχω άγχος.

In Greek, the definite article is used much more often than in English, even with general or abstract ideas.

So ο ύπνος can mean sleep in a general sense, not only the sleep in a very specific sense.

Here, ο also tells you useful grammar information:

• ο = masculine singular nominative
• so ο ύπνος is the subject of the sentence

English often drops the article in sentences like Sleep helps me, but Greek normally keeps it.

Ο ύπνος is the subject: the thing doing the helping.

You can break the sentence down like this:

• ο ύπνος = the subject
• με = me
• βοηθάει = helps
• όταν έχω άγχος = when I have stress/anxiety

A big clue is the article ο, which marks ύπνος as nominative masculine singular, the form typically used for the subject.

Yes — με can mean two different things:

• με = me as an object pronoun
• με = with as a preposition

In this sentence, it means me because it appears right before the verb:

• με βοηθάει = helps me

If it meant with, it would normally be followed by a noun:

• με τον φίλο μου = with my friend

So here με is not the preposition with. It is the weak object pronoun me.

In Modern Greek, weak object pronouns like με, σε, τον, τη(ν), μας usually come before a finite verb.

So Greek says:

• με βοηθάει = it helps me

not:

• βοηθάει με

This is normal Greek word order for object pronouns.

One important exception: with commands, the pronoun usually comes after:

• Βοήθησέ με. = Help me.

Yes, βοηθάει and βοηθά are both correct.

They are two common forms for he/she/it helps from the verb βοηθάω / βοηθώ.

So these are both natural:

• Ο ύπνος με βοηθάει.
• Ο ύπνος με βοηθά.

The version with -άει is very common in everyday speech and writing.

Because it expresses a general or habitual truth:

• Sleep helps me when I have stress/anxiety.

This is not about one single event right now. It means that this is generally true whenever that situation happens.

Greek, like English, often uses the present tense for this kind of meaning:

• με βοηθάει
• έχω

Όταν means when, and in sentences like this it often has the sense of whenever.

So:

• όταν έχω άγχος = when / whenever I have stress

Because the verb after it is in the present tense (έχω), the whole clause sounds habitual:

• whenever I feel stressed
• when I have anxiety/stress

Greek very often uses έχω + noun where English might use be + adjective.

So:

• έχω άγχος = literally I have stress/anxiety
• natural English: I’m stressed, I’m anxious, I have anxiety

This is a very common Greek pattern:

• έχω φόβο / φοβάμαι type differences
• έχω κούραση in some contexts
• έχω όρεξη = I feel like / I’m in the mood for

So έχω άγχος is a normal, idiomatic Greek way to express that state.

Because έχω άγχος is an idiomatic expression, and abstract nouns after έχω often appear without the article.

So:

• έχω άγχος = I have stress/anxiety

This sounds natural and general.

If you added an article, it would usually sound more specific or less natural in this context. For a learner, the safest thing is to remember έχω άγχος as a set phrase.

It can mean either, depending on context.

Common possibilities:

• stress
• anxiety
• nervous tension
• sometimes worry

In everyday Greek, άγχος is very often used where English speakers would say stress:

• Έχω άγχος για τις εξετάσεις. = I’m stressed about the exams.

But in some contexts it can be closer to anxiety.

Yes. Greek word order is more flexible than English word order.

The original sentence:

• Ο ύπνος με βοηθάει όταν έχω άγχος.

is a neutral way to say it.

But these are also possible:

• Με βοηθάει ο ύπνος όταν έχω άγχος.
• Όταν έχω άγχος, ο ύπνος με βοηθάει.

The basic meaning stays the same, but the emphasis shifts:

• putting με βοηθάει first can emphasize the action
• putting όταν έχω άγχος first sets the scene first

Yes. Ύπνος is a masculine noun.

That is why it takes:

• ο ύπνος in the nominative singular

This is something learners simply need to memorize with the noun:

• ο ύπνος = sleep

In Greek, every noun has grammatical gender, and it does not always match anything logical from English. So it is best to learn nouns together with their article.