No golpees la mesa.

Because this sentence uses a negative tú command: No golpees.

In Spanish, negative commands for tú use the present subjunctive, not the normal present tense.

• Present tense: tú golpeas = you hit / you are hitting
• Negative command: no golpees = don’t hit

So golpeas describes an action, but golpees gives an instruction or order.

Yes. It is a negative informal command addressed to one person.

It is the tú form, so it is used when speaking informally to someone you would normally call tú.

Examples:

• Golpea la mesa. = Hit the table.
• No golpees la mesa. = Don’t hit the table.

So the sentence is telling someone not to do something.

That is simply the normal grammar pattern in Spanish.

For commands:

• affirmative tú commands usually use a special command form based on the verb:
  
  • habla, come, vive
• negative tú commands use the present subjunctive:
  
  • no hables, no comas, no vivas

So:

• golpea = hit!
• no golpees = don’t hit!

It may feel strange to an English speaker because English does not change the verb in this way, but in Spanish this is standard.

In Spanish, no normally goes before the verb to make it negative.

So:

• Golpeas la mesa. = You hit the table.
• No golpees la mesa. = Don’t hit the table.

This is the normal position for no in Spanish.

It is understood, so Spanish usually leaves it out.

No golpees la mesa already tells you the subject is tú because of the verb form golpees.

You could say:

• Tú no golpees la mesa

But that is usually unnecessary unless you want to add emphasis, contrast, or clarity.

Spanish often omits subject pronouns when the verb already makes the subject clear.

Spanish often uses the definite article more often than English does.

Here, la mesa means the table. In a normal sentence like this, Spanish usually keeps the article:

• No golpees la mesa.

Leaving it out would sound unnatural in standard Spanish unless you were using a special style, like a label, headline, or note.

A simple guide is:

gol-PE-es

There are three syllables:

• gol
• pe
• es

The stress falls on pe.

The ee sound is not one long English vowel. It is really two vowels next to each other:

• gol-pe-es

In Spain, a careful pronunciation would sound roughly like: gol-PEH-es

It comes from golpear, which means to hit, to strike, or to bang.

To form the subjunctive:

1. Start with the yo form of the present tense: golpeo
2. Remove the -o
3. Add the subjunctive ending for tú: -es

So:

• golpeo
• golpee-
• golpees

That gives no golpees.

Yes.

This sentence is the tú version. Other forms are:

• tú: No golpees la mesa.
• usted: No golpee la mesa.
• vosotros: No golpeéis la mesa.
• ustedes: No golpeen la mesa.

Since you mentioned Spanish from Spain, vosotros is especially important:

• No golpeéis la mesa = Don’t hit the table, talking to more than one person informally in Spain

You might hear other verbs depending on context, but golpear is a good, clear verb for hitting/striking.

A few possibilities:

• golpear = to strike, hit, bang
• pegar = to hit, but also to stick/glue, so it has more meanings
• dar golpes a = to bang on / to knock on / to hit repeatedly

So No golpees la mesa is completely natural for Don’t hit/bang the table.

In some contexts, No le pegues a la mesa could also be heard, but it is not the same structure and may sound a bit different in nuance.

By itself, it can mean either, depending on context.

No golpees la mesa can mean:

• don’t hit the table
• don’t bang on the table
• don’t keep striking the table

If you want to make repetition clearer, Spanish can use other wording, such as:

• No estés golpeando la mesa
• No des golpes en la mesa

But the original sentence is a normal and natural way to tell someone not to hit or bang the table.

It depends mostly on tone of voice and context.

Grammatically, it is just a straightforward negative command in the tú form. It can sound:

• neutral
• firm
• annoyed
• protective

If you want to sound softer, Spanish often adds polite expressions, for example:

• No golpees la mesa, por favor.
• Por favor, no golpees la mesa.

So the grammar itself is not automatically rude, but the situation and tone matter a lot.