Ela ligou o aspirador sem ler o manual e depois não conseguiu desligar.

Yes, ligar can mean to call, but it also very commonly means to turn on a device.

So in this sentence:

• ligou o aspirador = turned on the vacuum cleaner

Portuguese often uses ligar for switching something on:

• ligar a TV = turn on the TV
• ligar o computador = turn on the computer

The opposite is desligar = to turn off.

Context tells you which meaning ligar has.

Yes. Aspirador here means vacuum cleaner, especially when the context is clear.

In full, people may say:

• aspirador de pó = vacuum cleaner

But in everyday speech, aspirador is often enough.

So:

• ligou o aspirador = turned on the vacuum cleaner

After sem when you mean without doing something, Portuguese normally uses the infinitive.

So:

• sem ler = without reading
• sem pensar = without thinking
• sem falar = without speaking

That is why:

• sem ler o manual = without reading the manual

Using leu would not work here, because leu is a finite past-tense form, while sem needs the infinitive in this structure.

Because conseguiu desligar means managed to turn off or was able to turn off, while não conseguiu desligar means didn’t manage to turn it off.

This adds the idea of ability/success.

Compare:

• desligou = she turned it off
• não desligou = she didn’t turn it off
• não conseguiu desligar = she couldn’t manage to turn it off

So conseguir + infinitive is a very common pattern in Portuguese:

• conseguiu abrir = managed to open
• não conseguiu encontrar = couldn’t find

Because Portuguese often leaves out the object when it is already obvious from context.

Here, we already know the object is o aspirador, so saying just:

• não conseguiu desligar

naturally means:

• she couldn’t turn it off

If you wanted to make the object explicit, you could say:

• não conseguiu desligá-lo

That means the same thing, but it sounds a bit more explicit and sometimes a bit more formal or careful. In everyday speech, leaving it out is very common.

In Portuguese, não normally goes before the verb it negates.

So:

• não conseguiu = did not manage
• não leu = did not read
• não desligou = did not turn off

That is the standard position for negation in simple statements.

They are both in the pretérito perfeito (the simple past / preterite).

In this sentence:

• ligou = she turned on
• conseguiu = she managed / was able

This tense is used for completed actions in the past.

Here are the infinitives and forms:

• ligar → ela ligou
• conseguir → ela conseguiu

This is one of the most common past tenses in Brazilian Portuguese.

The infinitive is ler = to read, and after sem we use the infinitive, so ler is exactly the form we want.

The past form would be different:

• ela leu = she read

So in the sentence:

• sem ler o manual = without reading the manual

There is nothing irregular in that part; it is just the infinitive.

What may feel surprising is that read in English looks the same in writing in present and past, but Portuguese changes clearly:

• ler = to read
• leu = read (past)

Depois means afterward / later / then, and its position is somewhat flexible.

In your sentence:

• ... e depois não conseguiu desligar.

This is very natural.

You could also hear:

• Ela ligou o aspirador sem ler o manual e não conseguiu desligar depois.

But that version may sound slightly different in emphasis. The original placement is smoother and more natural for most contexts.

So yes, depois can move, but where it appears affects rhythm and emphasis.

They can both relate to turning something off, but they are not used in exactly the same way.

• desligar is very common for machines, devices, electronics:

  • desligar o aspirador
  • desligar o computador
  • desligar a TV

• apagar is often used for lights or flames:

  • apagar a luz = turn off the light
  • apagar a vela = put out the candle

So for a vacuum cleaner, desligar is the natural choice.

Yes, but the nuance is a little different.

• não conseguiu desligar = she didn’t manage to turn it off / couldn’t turn it off
• não pôde desligar = she was not able to turn it off / could not turn it off

In many contexts they are close, but não conseguiu often suggests an attempt that failed, while não pôde can sound more like lack of possibility or permission, depending on context.

In this sentence, não conseguiu desligar is very natural because it suggests she tried and failed.

Because both actions have the same subject, and Portuguese does not need to repeat it.

So:

• Ela ligou o aspirador ... e depois não conseguiu desligar.

The subject ela is understood for both verbs.

You could repeat it:

• Ela ligou o aspirador sem ler o manual e depois ela não conseguiu desligar.

But that is usually unnecessary unless you want special emphasis or contrast.

Yes. This sentence uses a very common storytelling pattern:

• action 1 in the past: Ela ligou o aspirador
• extra detail with infinitive: sem ler o manual
• action/result after that: e depois não conseguiu desligar

This kind of structure is extremely natural in Portuguese for narrating events:

• Ele saiu sem avisar e depois voltou tarde.
• Ela abriu o arquivo sem salvar a cópia e depois perdeu tudo.

So the sentence is a good example of everyday connected past narration.