Apesar de o micro-ondas estar ligado, o pão ainda não esquentou; acho que ele saiu do freezer há pouco tempo.

Apesar de is a very common expression meaning despite or in spite of. It introduces a contrast:

• Apesar do frio, saímos. = despite the cold
• Apesar de estar cansado, ele continuou. = despite being tired

In your sentence, it introduces the idea that one thing is true, but the expected result did not happen.

This is a point many learners notice.

Normally, de + o = do. So in many situations, a contraction is expected. But when o micro-ondas is the subject of an infinitive clause (o micro-ondas estar ligado), more careful or formal grammar often prefers de o rather than do:

• apesar de o micro-ondas estar ligado

This helps show that o micro-ondas belongs with estar ligado, not directly with apesar de.

That said, in everyday Brazilian Portuguese, many people would naturally say:

• apesar do micro-ondas estar ligado

So:

• de o = more formal / more conservative grammar
• do = very common in real-life speech and informal writing

After apesar de, Portuguese commonly uses an infinitive structure:

• apesar de estar ligado
• apesar de chover
• apesar de ser tarde

So estar is in the infinitive because it is part of the structure introduced by apesar de.

Here, o micro-ondas is the subject of that infinitive clause:

• o micro-ondas estar ligado

English usually would not build the sentence this way, so this structure can feel unusual at first.

Here, ligado means on, turned on, or switched on.

With appliances in Brazilian Portuguese:

• estar ligado = to be on
• estar desligado = to be off

Depending on context, ligado can also sometimes suggest plugged in or connected, but with micro-ondas, the most natural meaning here is turned on.

In this sentence, o micro-ondas is singular: the microwave.

This word keeps the same form in singular and plural:

• o micro-ondas = the microwave
• os micro-ondas = the microwaves

The article tells you whether it is singular or plural.

It is also masculine, which is why the sentence says o micro-ondas.

Esquentou is pretérito perfeito (simple past).

But in this kind of sentence, Portuguese often uses the simple past where English would more naturally use the present perfect:

• o pão ainda não esquentou
• literally: the bread still didn’t warm up
• natural English: the bread hasn’t warmed up yet

So this is a very useful pattern to notice:

• ainda não + pretérito perfeito often corresponds to not ... yet in English.

Ainda não means not yet.

It is extremely common and usually comes before the verb or verbal phrase:

• ainda não chegou = hasn’t arrived yet
• ainda não está pronto = isn’t ready yet
• ainda não esquentou = hasn’t warmed up yet

A good way to learn it is as a chunk: ainda não.

Yes, both verbs can be used, but they are not identical in feel.

• esquentar = very common, everyday, natural for food, drinks, and objects getting warm/hot
• aquecer = also correct, but often sounds a bit more neutral, technical, or formal

For everyday Brazilian Portuguese, o pão não esquentou sounds very natural.

Also, esquentar can be intransitive here:

• o pão esquentou = the bread warmed up

Because pão is a masculine noun.

In Portuguese, pronouns agree with the grammatical gender of the noun:

• o pão → ele
• a pizza → ela

So ele here does not mean the bread is being treated like a person. It is just normal grammatical agreement.

Literally, saiu do freezer means came out of the freezer.

In context, it means the bread was taken out of the freezer a short time ago. Portuguese often says this without mentioning who removed it, because that detail is not important.

So the focus is on the bread’s recent change of state/location, not on the person who took it out.

Also notice the contraction:

• de + o freezer = do freezer

Há pouco tempo means a short time ago.

Here, há is the verb haver used in an impersonal time expression, similar to ago in English:

• há dois minutos = two minutes ago
• há três dias = three days ago
• há pouco tempo = a short time ago

This is a very common structure in Portuguese.

Learners should be careful not to confuse:

• há = there is/are; ago
• a = the preposition to / at / for

Yes. In Brazilian Portuguese, faz pouco tempo is also very common and natural.

So these are both possible:

• ele saiu do freezer há pouco tempo
• ele saiu do freezer faz pouco tempo

Both mean basically the same thing. Há pouco tempo is a little more traditional in grammar explanations, but faz pouco tempo is extremely common in Brazil.

The semicolon links two closely related ideas:

1. the microwave is on, but the bread has not warmed up
2. the speaker’s explanation: it probably came out of the freezer recently

A semicolon is a punctuation choice, not a special grammar rule here. A period would also work, and in less formal writing, many people might use a comma. The semicolon just gives a slightly more structured written feel.