L'avversario prepara il gioco da tavolo.

Because lo is the masculine singular definite article used before certain consonant sounds, and before a vowel it usually shortens to l'.

So:

• lo avversario → l'avversario

This is called elision. Italian does this to make pronunciation smoother.

A few related examples:

• lo studente
• l'amico
• l'uomo

So l'avversario means the opponent, with l' standing for the article.

Avversario means opponent, adversary, or sometimes rival, depending on context.

It is common in:

• sports
• games
• competitions
• debates or conflicts

So it is not limited to sports. In this sentence, it simply refers to the person on the other side, likely in a game situation.

Il is the masculine singular definite article, meaning the.

Here, gioco is a masculine singular noun, so it takes il:

• il gioco

Then da tavolo describes what kind of game it is:

• il gioco da tavolo = the board game

So the whole noun phrase is:

• il = the
• gioco = game
• da tavolo = board / for the table

Literally, da tavolo means something like for the table or of the table, but in natural English it corresponds to board in board game.

In Italian, da + noun is often used to describe the purpose or type of something.

Examples:

• occhiali da sole = sunglasses
• spazzolino da denti = toothbrush
• gioco da tavolo = board game

So da tavolo is not about movement from the table here. It describes the category of the game.

Preparare is the infinitive, meaning to prepare.

Prepara is the third-person singular present tense form:

• io preparo = I prepare
• tu prepari = you prepare
• lui/lei prepara = he/she prepares

Since the subject is l'avversario = the opponent, Italian uses the he/she/it form:

• L'avversario prepara = The opponent prepares / is preparing

It can mean either, depending on context.

Italian present tense often covers both:

• The opponent prepares the board game
• The opponent is preparing the board game

Italian does not always separate simple present and present progressive the same way English does. If the context strongly emphasizes an action in progress, Italian can also use:

• sta preparando

But prepara is completely normal and very common.

This is the standard Italian word order:

subject + verb + object

• L'avversario = subject
• prepara = verb
• il gioco da tavolo = object

Italian word order is somewhat flexible, but this version is the most neutral and natural.

You might change the order for emphasis, for example:

• Il gioco da tavolo lo prepara l'avversario

That sounds more marked, as if emphasizing it is the opponent who prepares the board game.

For a basic sentence, the original order is best.

A simple pronunciation guide is:

lahv-ver-SAH-ryo pre-PA-ra eel JWO-ko da TA-vo-lo

A few notes:

• avversario has double vv, so the consonant is held slightly longer.
• gioco starts with gio-, pronounced roughly like jwo.
• gli is not present here, so pronunciation is fairly straightforward.
• Stress usually falls like this:
  • avverSArio
  • prePAra
  • GIOco
  • TAvolo

In the sentence, it is singular:

• il gioco da tavolo = the board game

The plural is:

• i giochi da tavolo = the board games

Notice that:

• il → i
• gioco → giochi

da tavolo stays the same.

Yes. The feminine form is avversaria.

So you would get:

• L'avversaria prepara il gioco da tavolo.

That means the female opponent prepares the board game.

The verb prepara stays the same, because in the present tense the lui/lei form is identical.

Usually, yes, if the context already makes the subject clear.

Italian often drops subject pronouns, but here the subject is not a pronoun, it is a full noun phrase: l'avversario.

If the listener already knows who the opponent is, Italian could simply say:

• Prepara il gioco da tavolo.

That would mean something like:

• He/She is preparing the board game
• The opponent is preparing the board game

The subject is often omitted when it is understood from context or from the verb form.