Pendurei o casaco num cabide, para que a manga molhada não tocasse no chão.

Pendurei is the 1st person singular preterite of pendurar. It means I hung or I hung up and shows a completed action in the past.

Because the ending -ei already shows the subject is eu, Portuguese normally leaves eu out unless it is being emphasized.

O casaco means the coat/jacket. Portuguese uses definite articles much more often than English, especially when talking about a specific thing the speaker has in mind.

If you said um casaco, that would mean a coat/jacket, introducing it as less specific.

Num is a contraction of em + um.

So:

• em um cabide → num cabide

Even though English says on a hanger, Portuguese uses em here. So num cabide is the natural way to say on a hanger.

Cabide means hanger, especially a clothes hanger.

So pendurar o casaco num cabide is to hang the coat on a hanger.

Para que introduces a purpose clause: so that.

It is used here because the next part has a conjugated verb: tocasse.

• para que ... tocasse = so that ... would not touch
• If you used para without que, you would normally use the infinitive instead:
  • para a manga molhada não tocar no chão

Both are possible, but para que + subjunctive is a very common and clear structure.

Tocasse is the imperfect subjunctive of tocar.

After para que, Portuguese normally uses the subjunctive, because the clause expresses a purpose, not a simple fact.

Since the main verb is in the past (pendurei), Portuguese commonly uses the imperfect subjunctive in the purpose clause:

• Pendurei ... para que ... não tocasse ...

If the main verb were in the present or future, you would more likely see the present subjunctive:

• Penduro o casaco ... para que a manga molhada não toque no chão.

Yes. In this sentence, tocar means to touch.

This verb has several meanings in Portuguese, depending on context, including:

• to touch
• to play an instrument
• to ring or to sound

Here, because of no chão, the meaning is clearly touch.

Yes. Manga can mean either sleeve or mango, but here it clearly means sleeve because the sentence is about a coat.

Molhada agrees with manga:

• manga = feminine singular
• molhada = feminine singular

If the adjective described casaco instead, it would be:

• o casaco molhado

No is a contraction of em + o:

• em o chão → no chão

With tocar in the sense of physical contact, Portuguese very often uses tocar em something, so tocar no chão is very natural.

English usually says touch the floor with no preposition, but Portuguese often keeps the preposition here.

Also, chão can mean floor or ground depending on context. In this sentence, it clearly means floor.

The comma marks a pause before the purpose clause and helps readability, especially because the second part of the sentence is fairly long.

In similar sentences, you may sometimes see no comma. Here it is mainly a punctuation and style choice, not a change in meaning.