No puedo salir esta noche; además, tengo que terminar el informe.

In Spanish, the normal way to make a sentence negative is to put no directly before the conjugated verb:

• No puedo salir = I can’t go out

So:

• Puedo salir = I can go out
• No puedo salir = I can’t go out

Spanish does not usually put no at the end the way English can sometimes use extra negative wording.

Spanish often leaves out subject pronouns because the verb ending already shows who is doing the action.

• puedo = I can
• tengo = I have / I must in this structure

So No puedo salir... already clearly means I can’t go out...
You could say Yo no puedo salir..., but adding yo usually gives extra emphasis, such as contrast or insistence.

Here salir means to go out.

In Spanish, salir can mean several related things depending on context:

• leave
• go out
• go out socially

In No puedo salir esta noche, the most natural meaning is I can’t go out tonight, especially in the sense of going out in the evening.

Spanish often expresses tonight as esta noche, literally this night.

So:

• esta mañana = this morning
• esta tarde = this afternoon / this evening
• esta noche = tonight

This is completely normal and idiomatic in Spanish.

Además means besides, furthermore, or what’s more. It adds another reason or extra information.

In your sentence:

• No puedo salir esta noche; además, tengo que terminar el informe.
• I can’t go out tonight; besides/furthermore, I have to finish the report.

También usually means also / too, but it does not have the same strong sense of adding an extra reason.

Compare:

• Además, tengo que terminar el informe. = Besides, I have to finish the report.
• También tengo que terminar el informe. = I also have to finish the report.

Both are possible in some contexts, but además works better here because it strengthens the excuse or explanation.

The semicolon links two closely related ideas:

• No puedo salir esta noche
• además, tengo que terminar el informe

It shows a stronger pause than a comma, but not as full a break as a period.

You could also write:

• No puedo salir esta noche. Además, tengo que terminar el informe.

That is also correct.

In everyday writing, many people might choose a full stop instead of a semicolon. The semicolon just makes the connection between the two clauses feel especially close.

Tener que + infinitive is a very common structure meaning to have to do something.

So:

• tengo que terminar = I have to finish

Other examples:

• Tengo que estudiar = I have to study
• Tenemos que salir = We have to leave
• ¿Tienes que trabajar? = Do you have to work?

It expresses obligation or necessity.

Yes. Debo terminar el informe is grammatical and means I must / should finish the report.

But there is a slight difference in tone:

• tengo que = have to, more neutral and very common in everyday speech
• debo = must / should, sometimes a little more formal or stronger depending on context

In ordinary conversation, tengo que terminar el informe sounds very natural.

El informe means the report, referring to a specific report that both speaker and listener can identify, or that is already understood from context.

• Tengo que terminar el informe = I have to finish the report

If you said un informe, it would mean a report, more indefinite:

• Tengo que terminar un informe = I have to finish a report

Both are possible, but they do not mean exactly the same thing.

Yes, depending on context. Esta noche covers the evening/night period broadly, and English may translate it as:

• tonight
• sometimes this evening

If the context is going out socially after dark, tonight is usually the best translation.

Yes, but the sentence structure and nuance would change.

With porque:

• No puedo salir esta noche porque tengo que terminar el informe.
• I can’t go out tonight because I have to finish the report.

This is a direct cause-and-effect explanation.

With además:

• No puedo salir esta noche; además, tengo que terminar el informe.

This sounds like the speaker is adding another reason or reinforcing the first statement. It is a little more like Besides, I have to finish the report.

So both are correct, but they are not exactly the same in tone.

Yes, it works perfectly in Spanish from Spain, but it is also standard and natural in most of the Spanish-speaking world.

Nothing in the sentence is uniquely Spain-only in grammar. However, it fits very naturally with common Peninsular Spanish usage:

• salir for go out
• además in formal or neutral speech
• tengo que for obligation

So a learner of Spanish from Spain can use it confidently.