Το στήθος μου πονάει.

Word by word:

• Το = the
• στήθος = chest
• μου = my
• πονάει = hurts / is hurting

So the structure is literally The chest of me hurts, but natural English is My chest hurts.

Greek often uses the definite article with body parts, even when a possessive is also present.

So:

• το στήθος μου = literally the chest my
• natural English = my chest

This is very normal in Greek. You will see the same pattern in many expressions:

• το χέρι μου = my hand
• το κεφάλι μου = my head
• το πόδι μου = my leg

So the article is not strange or extra here; it is the normal Greek way to say it.

In Greek, the weak possessive form μου usually comes after the noun.

So Greek says:

• το στήθος μου = my chest

not normally:

• μου το στήθος

This post-noun position is standard for possessive pronouns like:

• μου = my
• σου = your
• του / της = his / her
• μας = our
• σας = your
• τους = their

Examples:

• το σπίτι μου = my house
• η φίλη σου = your friend
• το βιβλίο της = her book

πονάει is the 3rd person singular present form of πονάω / πονώ, meaning to hurt or to be in pain.

Here it agrees with το στήθος, which is singular:

• το στήθος μου πονάει = my chest hurts

You may also see:

• πονά instead of πονάει

Both are used in modern Greek. So these are both possible:

• Το στήθος μου πονάει
• Το στήθος μου πονά

They mean the same thing.

Yes. στήθος is a neuter noun.

That is why it takes:

• το in the singular nominative/accusative

So:

• το στήθος = the chest

Because it is the subject of the sentence here, it is in the nominative.

Yes. In Greek, μου is historically the genitive form of the pronoun, and it is used to express possession.

So μου can mean things like:

• my
• of me
• in some contexts, to me

In this sentence, it clearly means possession:

• το στήθος μου = my chest

This is very common in Greek: possession is often expressed with these short genitive pronouns after the noun.

Yes. Greek word order is more flexible than English.

Besides Το στήθος μου πονάει, you may also hear:

• Μου πονάει το στήθος
• Το στήθος μου με πονάει is less natural for this exact meaning, unless you mean something slightly different
• Με πονάει το στήθος is also very common

The most neutral version of your sentence is fine as it is:

• Το στήθος μου πονάει

But in everyday speech, many Greeks would also naturally say:

• Με πονάει το στήθος

That literally means The chest is hurting me, but in natural English it is still My chest hurts.

Both can mean My chest hurts, but the structure is different.

1. Το στήθος μου πονάει

   • literally: My chest hurts
   • the chest is the subject

2. Με πονάει το στήθος

   • literally: The chest hurts me
   • με = me, and the verb is used transitively

Greek often allows both patterns with πονάω. In everyday speech, Με πονάει... is extremely common when talking about body pain:

• Με πονάει το κεφάλι
• Με πονάει η μέση
• Με πονάει το πόδι

So the sentence you were given is correct, but it is useful to recognize the other very common pattern too.

A simple pronunciation guide is:

• Το ≈ toh
• στήθος ≈ STHEE-thos
• μου ≈ moo
• πονάει ≈ poh-NA-ee

A rough full pronunciation: toh STHEE-thos moo poh-NA-ee

A few notes:

• θ sounds like th in think
• ου sounds like oo in food
• The stress falls on:
  • στήθος
  • πονάει

Greek spelling follows its own stress rules. In πονάει, the written accent shows that the stress falls on νά:

• πονάει

In speech, this is often pronounced smoothly, something like poh-NA-ee.

You do not need to overthink the written accent here; just remember where the stress goes.

στήθος primarily means chest, especially in a general or anatomical sense.

Depending on context, it can sometimes refer to the breast area, but if someone specifically means a breast as a body part, Greek more often uses:

• στήθος for the chest area generally
• μαστός for breast, especially in medical or specific contexts

So in this sentence, στήθος is best understood as chest.

Yes, it is natural and correct.

That said, in everyday Greek, people often say:

• Με πονάει το στήθος
• Έχω πόνο στο στήθος = I have pain in my chest / I have chest pain

So your sentence is good Greek, but there are other very common ways to express the same idea.

To make it negative, use δεν:

• Το στήθος μου δεν πονάει = My chest does not hurt

To turn it into a yes/no question, Greek usually just uses intonation:

• Το στήθος μου πονάει; = Does my chest hurt? / Is my chest hurting?

In real conversation, context and tone do most of the work.

Yes, absolutely. This is a very useful pattern.

Examples:

• Το κεφάλι μου πονάει = My head hurts
• Η πλάτη μου πονάει = My back hurts
• Το πόδι μου πονάει = My leg hurts
• Το χέρι μου πονάει = My arm/hand hurts

So once you understand Το στήθος μου πονάει, you can build many similar sentences.