A Ana trouxe uma ligadura extra, porque a picada de mosquito ainda lhe dava comichão.

In European Portuguese, it is very common to use the definite article before a person's first name in everyday speech:

• A Ana
• O Pedro
• A Maria

So A Ana simply means Ana, not the Ana in any special emphatic sense.

The article is often omitted in:

• direct address: Ana, vem cá
• some formal writing
• headlines, lists, forms, etc.

This is a very normal European Portuguese feature.

Trouxe is the 3rd person singular preterite of trazer (to bring).

So:

• trazer = to bring
• trouxe = brought

Here it refers to a completed action in the past: Ana brought an extra bandage.

Compare:

• A Ana trouxe... = Ana brought...
• A Ana trazia... = Ana was bringing / used to bring...

The sentence uses trouxe because the act of bringing the bandage is seen as a completed event.

Here ligadura means a bandage or dressing.

In medical or everyday context, it refers to something used to cover or bind an injury. Depending on context, English might translate it as:

• bandage
• dressing

If you specifically mean a small adhesive bandage like a Band-Aid, European Portuguese often uses penso rápido instead.

So in this sentence, ligadura is best understood as bandage/dressing.

In Portuguese, extra often comes after the noun and means additional or spare.

So:

• uma ligadura extra = an extra bandage

That word order is very natural.

Also, extra is commonly treated as invariable, so it does not change here to match ligadura.

Compare:

• um saco extra
• uma ligadura extra
• horas extra

If you said outra ligadura, that would mean another bandage, which is similar but not exactly the same. Extra emphasizes that it is an additional one.

Porque means because.

In this sentence, it introduces the reason Ana brought the extra bandage:

• ...porque a picada de mosquito ainda lhe dava comichão.
• ...because the mosquito bite was still itchy / was still making her itch.

This is different from:

• por que = why / for which
• porquê = the reason
• por quê = why (usually at the end of a question)

So here porque is the correct form because it introduces a cause.

Picada de mosquito is the normal way to say mosquito bite.

This is a common Portuguese pattern:

• picada de mosquito = mosquito bite
• sumo de laranja = orange juice
• sapatos de couro = leather shoes

Here de mosquito describes the type/source of the bite, not a specific mosquito.

So:

• a picada de mosquito = the mosquito bite

If you said a picada do mosquito, that would sound more like the bite of the mosquito—as if you were talking about one specific mosquito already identified. That is possible in some contexts, but it is not the most natural choice here.

The article a means the here:

• a picada de mosquito = the mosquito bite

It suggests that this is a specific bite already known in the situation. Even if English might sometimes say a mosquito bite, Portuguese often uses the definite article when the thing is understood from context.

So the sentence is talking about that particular bite Ana had.

Ainda means still here.

So:

• ainda lhe dava comichão = was still making her itch / was still itchy

It shows that the itching had continued and had not gone away yet.

Depending on context, ainda can also mean things like:

• yet
• even
• still

But in this sentence, still is the right meaning.

Lhe means to her here, referring to Ana.

Portuguese uses lhe as an indirect object pronoun for him/her (and sometimes for you in formal address).

So the structure is roughly:

• a picada de mosquito dava comichão à Ana
• a picada de mosquito dava-lhe comichão

That literally means something like:

• the mosquito bite gave itchiness to Ana

In natural English, we would usually say:

• the mosquito bite was itchy
• the mosquito bite was making her itch

So lhe does not mean her as a direct object; it means to her.

Because porque normally triggers proclisis in European Portuguese, meaning the object pronoun goes before the verb.

So after porque, you get:

• porque ... lhe dava comichão

not usually:

• porque ... dava-lhe comichão

This is a common European Portuguese rule. Certain words and structures attract the pronoun before the verb, including:

• porque
• que
• não
• question words
• some subordinating conjunctions

So lhe dava is exactly what you would expect in this kind of clause.

This is an important vocabulary point.

In Portuguese, coçar usually means to scratch, not to itch.

So:

• coçar = to scratch
• dar comichão = to itch / to make someone itch
• ter comichão = to have an itch / to be itchy
• fazer comichão = to make itch

That means a picada de mosquito ainda lhe dava comichão is literally something like:

• the mosquito bite was still giving her itchiness

But in natural English, we translate it as:

• the mosquito bite was still itchy
• the mosquito bite was still making her itch

Also note that comichão is a noun meaning itch / itchiness.

Dava is the imperfect, and it is used because the itching is presented as an ongoing background condition.

So:

• ainda lhe dava comichão = it was still itching / still making her itch

This fits the idea that Ana brought the extra bandage because the bite continued to bother her.

If you used deu, that would sound more like a completed event:

• lhe deu comichão = it gave her an itch / it started itching / it caused itching at some point

That is a different nuance.

So the sentence uses:

• trouxe for the completed action
• dava for the continuing state in the background

This contrast is very typical in Portuguese.