У мене болить лоб.

Because Ukrainian often expresses physical sensations with a structure that is closer to At me, the forehead hurts than to I hurt.

So:

• у мене = at me / in my case
• болить = hurts / is aching
• лоб = forehead

This is a very common pattern with body parts:

• У мене болить голова. = My head hurts.
• У мене болять зуби. = My teeth hurt.

English says my forehead hurts, but Ukrainian commonly uses у мене instead of a possessive like мій.

Я is the nominative form, used for the subject of a sentence. But after the preposition у, Ukrainian uses a different case.

Here:

• я = I
• мене = a non-nominative form of I, used here after у

So у мене is a fixed and very common expression meaning at me / I have / in my case depending on context.

You will see it in many everyday sentences:

• У мене є брат. = I have a brother.
• У мене болить спина. = My back hurts.

Because the verb agrees with лоб, not with мене.

The grammatical subject here is лоб (forehead), which is singular. So the verb is singular:

• болить = singular
• болять = plural

Compare:

• У мене болить лоб. = My forehead hurts.
• У мене болять очі. = My eyes hurt.

So the important thing is: the thing that hurts controls the verb form.

Боліти is the verb to hurt / to ache / to be painful.

In this sentence, болить is the 3rd person singular form, because лоб is singular.

You can think of it as:

• лоб болить = the forehead hurts

Then у мене adds whose situation it is:

• У мене болить лоб. = My forehead hurts.

Yes, it is grammatically possible, but it is less natural in ordinary everyday speech.

• У мене болить лоб. is the normal, idiomatic way to say it.
• Мій лоб болить. sounds more emphatic or contrastive, as if you are stressing my forehead specifically.

In most neutral situations, a Ukrainian speaker would prefer У мене болить лоб.

In this sentence, лоб means forehead.

It refers to the front part of the head above the eyes. In some contexts it can also have related meanings like brow or the front of something, but for a learner, forehead is the main meaning to remember here.

So:

• лоб = forehead

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

The neutral version is:

• У мене болить лоб.

But other orders are possible, depending on emphasis:

• Лоб у мене болить. = emphasizes forehead
• Болить у мене лоб. = more marked, often stylistic or conversational

A good rule for learners: use У мене болить лоб as your default.

Both у and в can mean in/at in many contexts, and speakers often choose between them for ease of pronunciation.

So you may hear:

• У мене болить лоб.
• В мене болить лоб.

Both are normal. The choice often depends on sound and rhythm rather than meaning.

For learners, у мене is a very common form to memorize.

Then the verb usually changes to the plural form болять.

Compare:

• У мене болить лоб. = My forehead hurts.
• У мене болять очі. = My eyes hurt.
• У мене болять зуби. = My teeth hurt.

So:

• singular body part -> болить
• plural body part -> болять

Just add не before the verb:

• У мене не болить лоб. = My forehead doesn’t hurt.

This is the normal way to negate it.

Yes, very often.

Ukrainian commonly uses this pattern:

• У мене + болить / болять + body part

Examples:

• У мене болить голова. = My head hurts.
• У мене болить живіт. = My stomach hurts.
• У мене болять ноги. = My legs hurt.

So У мене болить лоб is part of a very useful everyday pattern.

A simple pronunciation guide is:

U me-NE bo-LYTʹ lob

A few helpful notes:

• мене has stress on the last syllable: меНЕ
• болить also has stress on the last syllable: болиТЬ
• ть at the end of болить is a soft consonant
• лоб is a short, clear one-syllable word

If you want a rough English-style approximation, you could think:

oo meh-NEH boh-LYTʹ lohp

But it is best to listen to native audio if possible.