L'uomo è ubriaco.

Because uomo begins with a vowel sound. In Italian, the masculine singular definite article il becomes l' before most words that start with a vowel.

So:

• il libro = the book
• l'uomo = the man
• l'amico = the friend

This shortening is called elision.

The apostrophe shows that a vowel has been dropped. Here, il loses its i before uomo, giving l'uomo.

So the apostrophe is not optional punctuation: it marks a real grammatical change.

The accent distinguishes è from e.

• è = is
• e = and

So in this sentence, è is the verb essere in the he/she/it is form.

Examples:

• L'uomo è ubriaco. = The man is drunk.
• pane e vino = bread and wine

A simple pronunciation guide is:

LOO-oh-moh eh oo-bree-AH-koh

A few details:

• uomo is pronounced roughly WOH-moh or OO-oh-moh, depending on how you break it down for learners, but in normal speech it flows smoothly.
• è is like eh
• ubriaco has the stress on a: u-bri-A-co

Italian pronunciation is usually very regular, so once you know the sounds, it becomes predictable.

In Italian, adjectives often come after the noun, especially when they describe a quality in a straightforward way.

So:

• un uomo ubriaco = a drunk man
• L'uomo è ubriaco = The man is drunk

With essere, the adjective normally comes after the verb:

• L'uomo è stanco.
• La donna è felice.

Yes. Ubriaco is an adjective meaning drunk. It describes the state of l'uomo.

In this sentence, it is a predicate adjective, meaning it comes after the verb è and tells you something about the subject.

Structure:

• L'uomo = subject
• è = verb
• ubriaco = adjective describing the subject

Yes. Italian adjectives usually change to agree with the noun in gender and number.

Forms of ubriaco:

• ubriaco = masculine singular
• ubriaca = feminine singular
• ubriachi = masculine plural
• ubriache = feminine plural

Examples:

• L'uomo è ubriaco.
• La donna è ubriaca.
• Gli uomini sono ubriachi.
• Le donne sono ubriache.

Because Italian uses essere = to be to describe states and qualities.

So:

• è ubriaco = is drunk

You would not say ha ubriaco for this meaning.

Compare:

• è stanco = is tired
• è felice = is happy
• è ubriaco = is drunk

Yes, it can. As an adjective, it means drunk. As a noun, it can mean drunkard or drunken person, depending on context.

Compare:

• L'uomo è ubriaco. = The man is drunk.
  
  • Here ubriaco is an adjective.
• L'uomo è un ubriaco. = The man is a drunkard / a drunk.
  
  • Here ubriaco is a noun.

The version with un ubriaco sounds stronger and more judgmental.

L'uomo è ubriaco is a complete sentence:
The man is drunk.

L'uomo ubriaco is just a noun phrase:
the drunk man or the drunken man

So the verb è is what turns it into a full statement.

Normally, no. In standard Italian, a singular countable noun like uomo usually needs an article or another determiner.

So you would say:

• L'uomo è ubriaco. = The man is drunk.
• Un uomo è ubriaco. = A man is drunk.

Saying just uomo è ubriaco would sound incomplete in ordinary Italian.

It is basically neutral and direct. Ubriaco is the normal everyday word for drunk.

Depending on tone and context, it can sound:

• factual: He is drunk
• critical: He is drunk
• descriptive: The man is drunk

So the word itself is not especially rude, but it can sound blunt because the idea is blunt.