Não toques no computador com as mãos molhadas.

Because this is a negative command addressed to tu.

The verb is tocar.

• tu tocas = you touch (normal present tense statement)
• não toques = don’t touch (negative command)

In European Portuguese, negative commands use the present subjunctive form, not the regular present indicative.

So:

• Tu tocas no computador. = You touch the computer.
• Não toques no computador. = Don’t touch the computer.

Yes — functionally, it is a command, but grammatically it is formed with the present subjunctive.

In Portuguese:

• Affirmative commands for tu usually use the imperative form:
  • Toca no computador. = Touch the computer.
• Negative commands use:
  • Não toques no computador. = Don’t touch the computer.

So learners often think:
negative imperative = não + present subjunctive

That is a very useful rule.

It is talking to one person in an informal way: tu.

The sentence does not include tu, because Portuguese often leaves the subject pronoun out when it is clear from the verb form.

• (Tu) não toques no computador...

The verb toques shows that the subject is tu.

If you wanted other versions, you could say:

• Não toque no computador... = formal singular (você / o senhor / a senhora)
• Não toquem no computador... = plural (vocês)

Because with tocar meaning to touch, Portuguese normally uses tocar em something.

So the structure is:

• tocar em + noun

Since computador is masculine singular and has the definite article o,
em + o = no

So:

• tocar no computador = to touch the computer

This is very important, because English says touch something, but Portuguese usually says touch in/on something with em.

Examples:

• Não toques na mesa. = Don’t touch the table.
• Não toques nos fios. = Don’t touch the wires.

No is a contraction of:

• em
  • o = no

So no computador literally comes from em o computador, but Portuguese contracts them.

Common contractions with em are:

• em + o = no
• em + a = na
• em + os = nos
• em + as = nas

Examples:

• na porta = in/on/at the door
• nos livros = in/on the books
• nas mãos = in/on the hands

In this sentence, no computador is just the normal way of saying the computer after tocar em.

This means with wet hands.

Breakdown:

• com = with
• as mãos = the hands
• molhadas = wet

So:

• com as mãos molhadas = with wet hands

It describes the condition of the hands while doing the action.

Because Portuguese often uses the definite article with body parts when the owner is obvious.

In English, we usually say:

• Wash your hands
• Don’t touch it with your wet hands

But in Portuguese, it is very natural to say:

• Lava as mãos.
• Não toques no computador com as mãos molhadas.

The idea of your is already understood from the context.

You can say com as tuas mãos molhadas, but it is usually less natural here unless you want extra emphasis.

Because molhadas agrees with mãos.

• mão is a feminine noun
• plural of mão is mãos
• therefore the adjective must also be feminine plural

So:

• mão molhada = wet hand
• mãos molhadas = wet hands

Agreement is very important in Portuguese:

• masculine singular: molhado
• feminine singular: molhada
• masculine plural: molhados
• feminine plural: molhadas

Yes. Mão is an irregular-looking noun and it is feminine:

• a mão = the hand
• as mãos = the hands

So you say:

• a mão esquerda
• as mãos molhadas

This is one of those nouns you simply need to remember.

In standard Portuguese from Portugal, that would usually sound unnatural for the meaning touch the computer.

The normal pattern is:

• tocar em algo
• so: Não toques no computador

Without em, tocar often suggests other meanings, especially in other contexts, such as:

• tocar guitarra = to play guitar

So for physical contact, tocar em is the safe choice.

Yes, but molhadas is the most natural everyday choice for wet here.

Possible alternatives:

• húmidas = damp/moist

But in this warning sentence, molhadas sounds more direct and natural:

• Não toques no computador com as mãos molhadas.

If your hands are clearly wet with water, molhadas is the best fit.

For a formal singular command, you would usually say:

• Não toque no computador com as mãos molhadas.

For plural:

• Não toquem no computador com as mãos molhadas.

So the verb changes depending on who you are addressing:

• tu → não toques
• você / o senhor / a senhora → não toque
• vocês → não toquem

Não is the normal word for not / don’t.

It goes before the verb:

• Não toques... = Don’t touch...

This is the standard position in Portuguese negative sentences and negative commands.

Examples:

• Não fales. = Don’t speak.
• Não abras a porta. = Don’t open the door.
• Não mexas nisso. = Don’t touch that / Don’t mess with that.

In European Portuguese, the pronunciation is more reduced than many learners expect.

Roughly:

• Não sounds like nowng / nasal now
• toques sounds roughly like TOH-ksh
• no computador may sound compressed, with unstressed vowels reduced
• mãos is nasal
• molhadas has lh like the lli in million for many English speakers

A rough learner-friendly approximation:

Nown TOH-ksh nuh koom-poo-tuh-DOR kong az maungsh moo-LYA-dush

This is only approximate, but the main things to notice are:

• nasal vowels in não and mãos
• reduced unstressed vowels
• lh in molhadas

A good summary is:

1. Negative command:

   • não + present subjunctive
   • Não toques

2. Informal singular:

   • addressed to tu

3. tocar em algo:

   • no computador

4. Body parts often use the definite article:

   • as mãos, not necessarily as tuas mãos

5. Adjective agreement:

   • mãos molhadas because mãos is feminine plural

This one sentence is a very good example of several core Portuguese patterns.