La instructora explica el cambio de pareja.

Because instructora is the feminine form, used for a female instructor. Spanish often changes -or to -ora for professions or roles:

• el instructor = a male instructor
• la instructora = a female instructor

The article also changes to match: la goes with feminine nouns.

In a normal sentence like this, yes, it sounds natural to use the article: La instructora...

Spanish uses articles more often than English does. English can say Instructor explains... only in special styles, but Spanish normally wants la instructora or una instructora.

• La instructora = the instructor
• Una instructora = an instructor

Explicar is the infinitive, meaning to explain.
Explica is the conjugated form, meaning explains.

Here it matches la instructora, which is she or the instructor:

• yo explico = I explain
• tú explicas = you explain
• él / ella explica = he / she explains

So La instructora explica... means The instructor explains...

Because Spanish usually leaves subject pronouns out when the verb already shows who is doing the action.

In explica, the ending tells us it is he/she/you (formal). Since the sentence already has la instructora, adding ella would usually be unnecessary.

• La instructora explica... = normal
• Ella explica... = possible, but only if you want emphasis or contrast

Because cambio is a masculine noun, so it takes the masculine singular article el.

• el cambio = the change

This is something you often just learn with the noun. Even though English uses the for everything, Spanish articles must match the noun’s gender and number.

Here de pareja works like partner change or change of partner, where pareja describes the type of change.

Spanish often uses de + noun this way without an article when speaking generally:

• cambio de pareja = partner change / change of partner
• clase de baile = dance class
• zapatos de cuero = leather shoes

If you said de la pareja, it would sound more like of the couple or of the partner, referring to a specific one.

Pareja can mean different kinds of partner, depending on context. It is not only a romantic partner.

Common meanings include:

• romantic partner
• dance partner
• partner in an activity
• one half of a pair/couple

In a sentence like La instructora explica el cambio de pareja, the context often suggests something like a class or activity where people switch partners, such as dancing.

Because grammatical gender and real-life sex are not always the same thing.

The noun pareja is grammatically feminine, so it uses feminine articles and adjectives:

• la pareja
• una pareja

But it can refer to:

• a female partner
• a male partner
• a couple

So the word is grammatically feminine no matter who the partner is.

Because el cambio is the direct object of explica, and explicar takes a direct object without a.

• La instructora explica el cambio = The instructor explains the change

Spanish only uses the personal a before specific people (and sometimes personified animals), not before things or ideas.

Compare:

• Explica el cambio = explains the change
• Ve a la instructora = sees the instructor

Yes. That would mean The instructor is explaining the partner change and it emphasizes that the action is in progress right now.

The simple present explica is very common in Spanish and can often cover both:

• explains
• is explaining (depending on context)

So both are possible, but explica is simpler and very natural.

Yes, depending on the context.

• el cambio de pareja = the partner change / the change of partner
• los cambios de pareja = the partner changes / partner changes

You might also hear cambio de parejas if the idea is more clearly about people switching among multiple partners in general. The exact choice depends on what the speaker wants to emphasize.

The normal order is:

La instructora + explica + el cambio de pareja

That is the most neutral and natural order: subject + verb + object.

Spanish can change word order for emphasis, but this basic version is the one learners should use first.

For example:

• La instructora explica el cambio de pareja. = neutral
• El cambio de pareja lo explica la instructora. = more emphatic/marked

It is pronounced roughly eks-PLEE-ka.

The stress is on the second syllable: pli.

A rough breakdown:

• ex = eks
• pli = plee
• ca = ka

So: eks-PLEE-ka.

Yes, depending on the situation. Some common alternatives are:

• la profesora = the teacher
• la monitora = the instructor/supervisor, often in activities
• la entrenadora = the trainer/coach

But instructora is perfectly correct if the person’s role is specifically that of an instructor.