A mi hermano no le gusta el cinturón; prefiere ponerse tirantes cuando lleva traje.

Yes — they both refer to my brother, and that is normal in Spanish.

In A mi hermano no le gusta el cinturón:

• A mi hermano = to my brother
• le = to him

Spanish often uses an indirect object pronoun (le) even when the person is also named explicitly.

So the structure is basically:

• A mi hermano → names the person
• le gusta → includes the required pronoun

This can:

• clarify who we are talking about
• add emphasis or contrast
• sound natural and standard

So Spanish prefers:

• A mi hermano no le gusta...

rather than just:

• A mi hermano no gusta... ❌

Because the thing doing the pleasing is el cinturón, which is singular.

With gustar, Spanish works differently from English. Instead of saying:

• My brother doesn’t like the belt

Spanish is closer to:

• The belt is not pleasing to my brother

So the grammar is:

• el cinturón = subject
• gusta = singular verb, matching el cinturón
• le = to him

If the thing liked/disliked were plural, you would use gustan:

• A mi hermano no le gustan los cinturones
  = My brother doesn’t like belts

Because gustar does not work like the English verb to like.

In English:

• My brother likes the belt

But in Spanish:

• The belt pleases my brother
• A mi hermano le gusta el cinturón

So with gustar:

• the person who likes something is usually an indirect object
• the thing liked is the subject

That is why mi hermano cannot be the subject of gustar in this sentence.

Using el cinturón here sounds like talking about the belt as an item / the belt in general in this context, not necessarily one specific belt you have already mentioned.

Spanish often uses the definite article more than English does, especially when talking about things in a general or familiar way.

So:

• no le gusta el cinturón = he doesn’t like wearing/using a belt
• no le gusta un cinturón would sound more like he doesn’t like a particular belt, or it would be less natural in this context

The sentence is really contrasting two clothing options:

• el cinturón
• tirantes

Here, tirantes means suspenders in British English or braces in British usage for trousers.

In Spain:

• tirantes = straps worn over the shoulders to hold trousers up

Important note for English speakers:

• In American English, suspenders can also mean lingerie straps in some contexts, but here it clearly means the clothing accessory for trousers.
• In Spain Spanish, tirantes is the normal word in this context.

Because ponerse means to put on oneself.

The verb is:

• poner = to put
• ponerse = to put on

So:

• prefiere ponerse tirantes = he prefers to put on / wear suspenders

The reflexive pronoun shows that the person is putting the item on himself.

Compare:

• pone el libro en la mesa = he puts the book on the table
• se pone el abrigo = he puts on his coat

Yes, absolutely.

There is a small difference in nuance:

• ponerse tirantes = to put on suspenders
• llevar tirantes = to wear suspenders

In many contexts, both can sound natural.

Here:

• prefiere ponerse tirantes cuando lleva traje

means something like:

• he prefers to put on suspenders when he wears a suit

If you said:

• prefiere llevar tirantes cuando lleva traje

that would mean:

• he prefers to wear suspenders when he wears a suit

Both are fine; ponerse focuses a bit more on the act of putting them on.

Because in Spanish, with llevar + clothing, the article is often omitted when you mean to be wearing that type of clothing in a general sense.

So:

• lleva traje = he is wearing a suit / he wears a suit
• lleva un traje = he is wearing a suit, with slightly more focus on one suit
• lleva el traje = he is wearing the suit, a specific one already known

In this sentence, cuando lleva traje means:

• when he wears a suit
• when he is dressed in a suit

This is very natural Spanish.

Both can be possible, but llevar is very common for what someone is wearing.

• llevar traje = to wear a suit / to have a suit on
• vestir traje = to wear a suit, but it can sound a bit more formal or stylistic depending on context

For everyday Spanish, especially in spoken language, llevar is extremely common with clothes.

So cuando lleva traje is a very natural choice.

Preferir can be followed by:

• a noun
• an infinitive
• one option over another

In this sentence:

• prefiere ponerse tirantes

the structure is:

• prefiere
  • infinitive

This means:

• he prefers to put on suspenders

Other examples:

• Prefiere café = He prefers coffee
• Prefiere salir temprano = He prefers to leave early
• Prefiere esto a eso = He prefers this to that

Because Spanish usually follows the natural gustar pattern:

• [A + person] + [indirect object pronoun] + gustar + thing liked]

So:

• A mi hermano = to my brother
• le gusta = is pleasing to him
• el cinturón = the belt

This is the normal and most natural order.

You could rearrange parts for emphasis in some contexts, but this version is the standard, neutral one.

No simply negates the verb:

• le gusta = he likes it / it pleases him
• no le gusta = he doesn’t like it / it does not please him

In Spanish, no usually goes directly before the conjugated verb:

• no le gusta
• no quiere
• no lleva

The semicolon links two closely related ideas:

• A mi hermano no le gusta el cinturón
• prefiere ponerse tirantes cuando lleva traje

It shows a strong connection, almost like:

• My brother doesn’t like belts; he prefers suspenders when he wears a suit.

You could also use:

• a full stop
• sometimes a comma in informal writing
• y if you wanted a slightly different rhythm

But the semicolon works well because the second clause explains or contrasts with the first.

Yes, but it changes the meaning slightly.

• A mi hermano no le gusta el cinturón
  = he doesn’t like the belt / he doesn’t like wearing a belt as an item

• A mi hermano no le gustan los cinturones
  = he doesn’t like belts in general

The plural version sounds more clearly like a general opinion about belts as a category.

The singular with article can still express a general idea, especially in context, but the plural makes that general meaning more explicit.

Yes, if the context already makes it clear who he is.

For example:

• A él no le gusta el cinturón; prefiere ponerse tirantes cuando lleva traje.

That means:

• He doesn’t like the belt; he prefers to wear suspenders when he wears a suit.

But A mi hermano is more specific and clearer if you are introducing the person for the first time.