Depois que ela caiu, o cotovelo dela ficou vermelho, e o joelho também.

Depois que is used before a full clause with a conjugated verb:

• depois que ela caiu = after she fell

Depois de is used before a noun or an infinitive:

• depois da queda = after the fall
• depois de cair = after falling

So here, because ela caiu is a complete clause, depois que is the correct choice.

Caiu is the preterite form of cair (to fall).

• ela caiu = she fell

The preterite is used for a completed action in the past. In this sentence, her falling is a finished event.

Because in modern Portuguese spelling, caiu has no accent.

This often surprises learners because it looks like it might need one, but forms like:

• caiu
• saiu
• construiu

are written without an accent.

Ficar often means to become or to get.

So:

• ficou vermelho = became red / got red

This is different from estava vermelho, which would mean was red and describe a state rather than the change into that state.

Here, ficou vermelho emphasizes the result after the fall.

Because Portuguese often uses ficar to show a change of condition.

Examples:

• ficou triste = became sad
• ficou cansado = got tired
• ficou vermelho = became red

If you used estar, you would usually be describing the condition itself:

• o cotovelo estava vermelho = the elbow was red

So ficou is natural here because the elbow changed after the fall.

Both are possible, but dela is often clearer.

• o cotovelo dela = her elbow
• seu cotovelo can mean her elbow, but it can also mean your elbow or even his/their elbow depending on context

Because seu/sua can be ambiguous, Brazilian Portuguese very often prefers:

• dele = his
• dela = her

So o cotovelo dela is a very natural, clear choice.

Yes, very often it could.

A Brazilian Portuguese speaker might also say:

• Depois que ela caiu, o cotovelo ficou vermelho, e o joelho também.

Because the subject is already ela, it is usually understood that the elbow and knee are hers.

Portuguese commonly omits the possessive with body parts when the owner is obvious from context.

Portuguese often uses the definite article with body parts where English uses a possessive.

So Portuguese may say:

• o cotovelo
• o joelho

where English would usually say:

• her elbow
• her knee

This is very normal in Portuguese, especially when it is already clear whose body part is being discussed.

Because vermelho agrees with o cotovelo, which is:

• singular
• masculine

So:

• o cotovelo vermelho
• o cotovelo ficou vermelho

If the subject were feminine, you would use vermelha:

• a mão ficou vermelha

If it were plural masculine or mixed, you would use vermelhos:

• o cotovelo e o joelho ficaram vermelhos

This is a very common kind of ellipsis in Portuguese.

The full version would be:

• o joelho também ficou vermelho

But because the verb phrase is already understood, Portuguese can shorten it to:

• o joelho também

This works just like English sometimes does:

• Her elbow got red, and her knee too.

Yes, it can move depending on emphasis, but o joelho também is very natural.

Possible versions include:

• o joelho também
• também o joelho (more marked/literary)
• o joelho ficou vermelho também

In this sentence, o joelho também sounds simple and natural.

Usually, no. In standard Portuguese, you normally do not put a comma before e when simply joining two parts of a sentence.

So a more neutral version would be:

• Depois que ela caiu, o cotovelo dela ficou vermelho e o joelho também.

The comma before e is not impossible, but it feels more like a pause for style or emphasis than a basic requirement.

Sometimes yes, but keeping ela is very normal.

Portuguese often drops subject pronouns when the verb form already makes the subject clear. However, with caiu, the form could refer to:

• he fell
• she fell
• you fell (formal)

So ela caiu is helpful because it makes the subject explicit.

Yes. A more compact version would be:

• Depois que ela caiu, o cotovelo e o joelho dela ficaram vermelhos.

That version repeats less and combines the two body parts into one subject.

The original sentence is still perfectly understandable and natural, especially because it highlights the elbow first and then adds the knee too.