El escrito de alegaciones pertenece al expediente sancionador.

Here escrito means a written document, written submission, or formal written statement. In everyday Spanish, escrito can simply mean something written, but in legal or administrative language it often means a specific formal document.

So in this sentence, el escrito de alegaciones is not just some writing. It is a particular official document.

Not usually in this kind of Spanish legal context. This is a very important false friend.

In administrative and legal Spanish, alegaciones often means something like:

• representations
• statements in your defence
• objections
• arguments submitted to the authority

So escrito de alegaciones is often a document in which a person or company responds to an administrative procedure and sets out their arguments.

If an English speaker sees alegaciones and thinks allegations, that can be misleading.

The preposition de links the two nouns and means something like of here.

So:

• escrito = written document
• de alegaciones = of objections / of representations / containing the party’s arguments

This is a very common Spanish structure: noun + de + noun.

For example:

• carta de presentación
• solicitud de ayuda
• informe de evaluación

So escrito de alegaciones is literally something like document of representations, though in natural English you would translate it more idiomatically.

Pertenece is the third-person singular of pertenecer, which means to belong to.

Here it means that the document belongs to, forms part of, or is associated with the administrative case file.

In legal or administrative Spanish, pertenecer a can sound more formal than everyday English belongs to. In context, it may imply not only ownership, but also that the document is part of a specific official file or procedure.

Because al is the contraction of a + el.

So:

• pertenece a el expediente → incorrect
• pertenece al expediente → correct

This contraction is required whenever a is followed by the masculine singular article el, except in a few special cases such as when el is part of a proper name.

So pertenece al expediente sancionador means belongs to the sanctioning/disciplinary file.

This is a fixed kind of administrative/legal expression in Spain.

• expediente = file, case file, administrative record, dossier
• sancionador = sanctioning, punitive, relating to a penalty or sanction

So expediente sancionador refers to an official administrative procedure or file in which the administration may impose a sanction, fine, or penalty.

It is very formal and bureaucratic Spanish. A learner should understand it as a legal-administrative term, not ordinary everyday vocabulary.

In Spanish, descriptive adjectives often come after the noun.

So:

• expediente sancionador
• literally: file sanctioning
• naturally: sanctioning file or disciplinary/penalty case file

That word order is normal in Spanish, especially in formal and technical language.

If you changed the order, it would usually sound unnatural or would change the emphasis.

The subject is El escrito de alegaciones.

You can tell because the verb is pertenece, which is third-person singular, and the whole noun phrase is singular:

• El escrito = singular
• de alegaciones = just extra information describing the document

So the sentence structure is:

• El escrito de alegaciones = subject
• pertenece = verb
• al expediente sancionador = complement with a

Spanish often uses the definite article el / la / los / las where English might or might not use the.

Here both articles are natural because the sentence refers to specific, identifiable things:

• El escrito de alegaciones = the particular written submission
• al expediente sancionador = the particular sanctioning case file

In legal and administrative Spanish, this is especially common, because the documents and files are usually specific and already known in context.

Not necessarily in the everyday sense of ownership.

In this context, pertenece a often means more like:

• is part of
• corresponds to
• is attached to
• belongs within

So the sentence may be saying that the written submission is part of that official administrative file, not that the file owns it in a personal sense.

Yes. It sounds very much like formal administrative/legal Spanish from Spain.

Expressions such as:

• escrito de alegaciones
• expediente sancionador

are especially common in Spanish public administration, legal notices, and bureaucratic documents in Spain.

A native speaker would probably see this as official or technical language rather than casual speech.

A careful Spain Spanish pronunciation would be approximately:

el es-KREE-to de a-le-ga-THYO-nes per-te-NE-the al eks-pe-DYEN-te san-thyo-na-DOR

A few useful notes for Spain Spanish:

• c before e/i is often pronounced like th in think:
  pertenece, sancionador
• g before a is a normal hard g sound:
  alegaciones
• stress falls naturally on:
  • esCRIto
  • alegaCIOnes
  • perteneCE
  • expeDIENte
  • sancionaDOR

If you use Latin American pronunciation instead, that is also perfectly understandable, but in Spain the c sounds above are typically pronounced with th.