El informe refiere el problema.

Refiere is the third-person singular present tense form of referir.

• infinitive: referir
• yo: refiero
• tú: refieres
• él/ella/usted: refiere
• nosotros/nosotras: referimos
• vosotros/vosotras: referís
• ellos/ellas/ustedes: refieren

It is a stem-changing verb: e → ie when the stress falls on that syllable.

So with El informe as the subject, you need refiere.

Not always. This is a very common source of confusion.

In Spanish, there are two important patterns:

• referir algo = to recount, report, mention, relate something
• referirse a algo = to refer to something

So:

• El informe refiere el problema uses the non-reflexive verb and takes a direct object
• El informe se refiere al problema means The report refers to the problem

English refer often matches Spanish referirse a, not always plain referir.

Because here el problema is the direct object of refiere.

With non-reflexive referir, you can say:

• referir un hecho
• referir una historia
• referir el problema

But with referirse, you need a:

• se refiere al problema

So the presence or absence of a helps show which structure you are using.

Yes, and in many contexts that version sounds more natural to modern speakers.

Compare:

• El informe refiere el problema = the report reports/mentions/relates the problem
• El informe se refiere al problema = the report refers to the problem / is about the problem

The reflexive version is much more common in everyday Spanish when you mean to refer to.

The non-reflexive version can sound formal, literary, or less common, depending on context.

Because problema is a masculine noun.

Some Spanish nouns ending in -a are masculine, especially words of Greek origin, such as:

• el problema
• el sistema
• el tema
• el programa

So it must be:

• el problema
• not la problema

This is something English speakers often have to memorize noun by noun.

Because the verb refiere is in the third-person singular, and El informe is the noun phrase that logically performs the action.

So the structure is:

• El informe = subject
• refiere = verb
• el problema = direct object

In other words, the report is the thing doing the referring/reporting.

It is grammatically possible, but it may sound formal or a bit stiff in many everyday contexts.

Depending on the meaning, speakers in Spain might more naturally say:

• El informe menciona el problema = The report mentions the problem
• El informe trata el problema = The report deals with the problem
• El informe se refiere al problema = The report refers to the problem

So refiere is not wrong, but it is not always the most everyday choice.

Yes, but the basic order here is the most neutral one:

• El informe refiere el problema

That is subject + verb + object, which is very standard.

You could change the order for emphasis or style, but it may sound less neutral. For a learner, this sentence is the safest pattern to follow.

Yes. It is pronounced roughly as re-FYE-re.

The ie here forms part of the stem change, and you hear it clearly in speech.

So:

• referir
• refiere

This is the same kind of change you see in verbs like:

• preferir → prefiere
• sentir → siente

Here it is transitive, because it takes a direct object:

• el problema

That is why the sentence has a complete object after the verb.

By contrast, referirse a works with a prepositional complement:

• se refiere al problema

So learners should notice that these are two different constructions, even though they are related.