Learn Hardcore Spanish (Latin America): La secadora será revisada por la técnica mañana. - The dryer will be inspected by the technician tomorrow.

The past participle agrees with the subject of the passive, not with the agent. The subject is la secadora (feminine singular), so you need revisada. If it were masculine plural, you’d use revisados, etc.

Why use será revisada and not estará revisada?

Ser + participle (e.g., será revisada) expresses the passive action/event: “will be checked.”
Estar + participle (e.g., estará revisada) expresses the resulting state: “will be (already) checked/finished by then.” Example:
Mañana la secadora será revisada. (The checking will happen tomorrow.)
Mañana la secadora estará revisada. (By tomorrow, it will be in a checked state.)

Can I say va a ser revisada instead of será revisada?

Yes. Va a ser revisada is the periphrastic (going to) future and is very common in conversation. Será revisada can sound a bit more formal or neutral.

Can I use the “se” passive instead?

Yes, but then you can’t name the agent:

Allowed: Se revisará la secadora mañana.
Not allowed: Se revisará la secadora por la técnica. (The “se” passive doesn’t take a “por + agent.” Use the active voice if you need to name the agent: La técnica revisará la secadora…)

Why is it por and not para to introduce the agent?

In Spanish passive constructions, the agent is introduced by por: …revisada por la técnica. Para expresses purpose/recipient, not the agent of an action.

Where can I put mañana in the sentence?

Common options:

Mañana la secadora será revisada por la técnica.
La secadora será revisada por la técnica mañana. You can also say La secadora será revisada mañana por la técnica. Inserting it between será and revisada (será mañana revisada) is possible but sounds more formal/literary.

Can the agent phrase por la técnica move around?

Yes, but it usually follows the participle or comes at the end:

La secadora será revisada por la técnica mañana.
La secadora será revisada mañana por la técnica. Placing it much earlier (e.g., right after the subject) is uncommon in speech.

Does la técnica mean “the female technician” or “the technique”?

Here it means “the female technician.” After a passive with por, Spanish expects an agent (a doer), so por la técnica strongly points to a person. If you meant “by means of the technique,” you’d say con la técnica or mediante la técnica.

What if the technician is male?

Use por el técnico. The job title técnico/técnica has a regular feminine: la técnica. Using la técnico is heard in some places but the standard feminine is la técnica.

Do I need the article before técnica?

Yes, if you mean a specific person:

Specific: por la técnica (“by the technician” we have in mind)
Non-specific: por una técnica (“by a technician”) Dropping the article (por técnica) changes the meaning and is not how you name the agent.

Does secadora mean clothes dryer or hair dryer?

In Latin America, la secadora most commonly means a clothes dryer (the appliance paired with la lavadora). A hair dryer is often el secador (de pelo/cabello) or la secadora de cabello in some countries. Context tells you which one is meant.

Why not secador here?

Secadora is standard for the laundry appliance. Secador tends to refer to a hair dryer or a device that dries in general. For the home laundry machine, secadora is the usual word alongside lavadora.

Does revisar mean “to repair”?

No. Revisar is “to check/inspect.” If you want “repair,” use reparar or arreglar.

Check: La secadora será revisada…
Repair: La secadora será reparada… Synonyms for “check” include inspeccionar, verificar; regionally you’ll also hear checar (Mexico) or chequear (Caribbean, Río de la Plata).

How would the sentence change for plurals?

Plural subject: Las secadoras serán revisadas por la técnica mañana.
Plural agent: La secadora será revisada por las técnicas mañana. The participle and the verb agree with the subject (secadora/secadoras), not with the agent.

Any quick pronunciation tips for this sentence?

será: stress the last syllable (seh-RAH); the accent mark shows this.
técnica: stress the first syllable (TEHK-nee-kah); the accent mark is required.
mañana: the ñ is like “ny” in “canyon” (mah-NYAH-nah).
revisada: Spanish b/v sound the same; say reh-bee-SAH-dah.

How do I say “tomorrow morning” here?

You can say:

Mañana por la mañana (neutral)
Mañana en la mañana (very common in Latin America) Example: La secadora será revisada mañana por la mañana.

Is the passive voice common in Spanish?

It exists but is less common in conversation than in English. Spanish often prefers:

Active: La técnica revisará la secadora mañana.
“Se” passive/impersonal: Se revisará la secadora mañana.

How is this passive formed and how can I change tenses?

It’s ser + past participle (+ por + agent). Common tenses:

Present: La secadora es revisada…
Preterite: La secadora fue revisada…
Imperfect: La secadora era revisada…
Future: La secadora será revisada…
Near future: La secadora va a ser revisada…
Perfect: La secadora ha sido revisada…

Any spelling/diacritic details I should watch?

será must have the accent on the final a.
técnica must have the accent on the first e (esdrújula).
mañana has the letter ñ (no acute accent). Writing manana changes the sound and is incorrect.