Quando a criança faz birra no parque infantil, a Ana tenta acalmá-la sem levantar a voz.

Fazer birra is a very common expression meaning to have a tantrum, to sulk, or to make a fuss, depending on context.

In this sentence, a criança faz birra means the child is behaving like a child having a tantrum.

It is not usually translated word-for-word. Learners should treat fazer birra as a set expression.

Examples:

• A criança está a fazer birra. = The child is having a tantrum.
• Não faças birra. = Don’t make a fuss / Don’t throw a tantrum.

Both are possible, but they mean slightly different things.

• faz birra = simple present; often used for habits, general situations, or vivid narration
• está a fazer birra = is having a tantrum right now, at this moment

In your sentence, Quando a criança faz birra... sounds like Whenever the child throws a tantrum... or When the child has a tantrum..., so the simple present fits well.

This is very common in Portuguese when describing repeated or typical situations.

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

• a Ana
• o João
• a Maria

So a Ana simply means Ana.

This is much more natural in Portugal than in English, where we normally do not use the before people’s names. It is a normal feature of Portuguese, especially in everyday speech.

Parque infantil means playground or children’s playground.

Literally:

• parque = park
• infantil = for children / children’s

In Portugal, parque infantil is the usual term for the place with swings, slides, climbing frames, and so on.

Because Portuguese uses an object pronoun here, not a stressed subject pronoun.

• ela = she / her, but mainly as a subject pronoun or after prepositions
• a = her, as a direct object pronoun

Since Ana tries to calm her, her is the direct object, so Portuguese uses the clitic pronoun a.

The base structure is:

• acalmar + a = to calm her

In European Portuguese, that pronoun is attached to the infinitive with a hyphen:

• acalmar-a

But because of a spelling change after verbs ending in -r, it becomes:

• acalmá-la

So tenta acalmá-la = tries to calm her

This is a very important spelling and pronunciation pattern in Portuguese.

When a clitic pronoun like o, a, os, as attaches to an infinitive ending in -r, the -r drops, and the vowel before it usually gets an accent.

So:

• acalmar + a → acalmá-la
• ver + o → vê-lo
• fazer + o → fazê-lo

Also, the pronoun changes to lo / la / los / las after certain final consonants are lost.

So this is not random: it is a regular pattern you will see often in formal writing and standard European Portuguese.

This is because European Portuguese strongly prefers enclisis in many contexts, meaning the pronoun comes after the verb and is attached with a hyphen.

So:

• acalmá-la = to calm her

In many other varieties, especially Brazilian Portuguese, learners often see more pronouns before the verb. But in European Portuguese, after an infinitive, attaching the pronoun is very normal and standard.

Here:

• tenta acalmá-la = tries to calm her

This sounds natural in Portugal.

Literally, it means without raising the voice.

Naturally in English, that is:

• without raising her voice
• without speaking loudly
• without shouting

The expression levantar a voz is very common in Portuguese and works a lot like raise one’s voice in English.

Examples:

• Não levantes a voz! = Don’t raise your voice!
• Falou sem levantar a voz. = He/She spoke without raising his/her voice.

Portuguese often uses the definite article where English uses a possessive.

So instead of saying:

• sem levantar a sua voz

Portuguese very naturally says:

• sem levantar a voz

The possessor is understood from the subject, which here is Ana. So it means without raising her voice.

This is very common with body parts, clothing, and things closely connected to the person:

• lavou as mãos = washed his/her hands
• fechou os olhos = closed his/her eyes
• levantou a voz = raised his/her voice

Using a sua voz is possible in some contexts, but here it sounds less natural and less idiomatic.

Criança is a grammatically feminine noun, no matter whether the child is a boy or a girl.

So you say:

• a criança

even if you are talking about a male child.

This is grammatical gender, not biological sex. Portuguese has many nouns like that.

If you later want to refer to the actual child with a pronoun, context may determine whether you use ele or ela, depending on whether the child is a boy or a girl.

The sentence begins with a quando clause:

• Quando a criança faz birra no parque infantil

This is an introductory subordinate clause, and it is followed by the main clause:

• a Ana tenta acalmá-la sem levantar a voz

Using a comma here is standard and helps separate the two parts clearly.

So the structure is:

• When X happens, Y happens.

The present tense here describes a typical or repeated situation, not just one single event.

• faz = does / has / throws
• tenta = tries
• levantar = to raise

So the sentence suggests something like:

• Whenever the child throws a tantrum at the playground, Ana tries to calm her without raising her voice.

This is a very common use of the present tense in Portuguese, just as in English when talking about habits or repeated actions.