Imprimo las diapositivas por si el proyector falla.

I print the slides in case the projector fails.

Breakdown of Imprimo las diapositivas por si el proyector falla.

• yo: I
• fallar: to fail
• imprimir: to print
• la diapositiva: the slide
• por si: in case
• el proyector: the projector

Questions & Answers about Imprimo las diapositivas por si el proyector falla.

Why is it falla and not falle or fallará after por si?

With por si the default is the present indicative: por si el proyector falla. Using the future (fallará) is ungrammatical here, and the present subjunctive (falle) is not used after por si in standard Spanish. You may see the imperfect subjunctive (por si fallara) to suggest a very remote possibility, but it’s rare in Latin America and more formal.

Can I say por si acaso instead of por si?

Yes. Por si acaso is basically the same as por si, often a bit more emphatic or colloquial: Imprimo las diapositivas por si acaso el proyector falla. Both typically take the indicative.

What’s the difference between por si and en caso de que?

• Por si + indicativo: a precaution for a possible event. Natural and neutral: Imprimo… por si falla.
• En caso de que + subjuntivo: a contingency clause, somewhat more formal or structured: Imprimo… en caso de que el proyector falle.

Why not simply si el proyector falla?

Si el proyector falla, imprimo… means you’ll print only after it fails (reactive). Imprimo… por si el proyector falla means you print in advance as a precaution (proactive). Different timing and intent.

Why the definite article las diapositivas? Could it be unas diapositivas or zero article?

• Las diapositivas: a specific, known set (the slides for this presentation).
• Unas diapositivas: some slides, an indefinite set.
• Zero article (Imprimo diapositivas) is possible but sounds more generic/habitual (“I print slides”), not “the slides” for this talk.

Is imprimo a present used for a near-future plan? Could I say voy a imprimir or imprimiré?

Yes, Spanish uses the present for near-future plans. You can also say:

• Voy a imprimir… (very common, neutral future)
• Imprimiré… (slightly more formal/distant or a spontaneous decision)

Could I say Estoy imprimiendo here?

Yes, if you mean the action is happening right now: Estoy imprimiendo las diapositivas por si el proyector falla. The original Imprimo… can be habitual or a near-future plan.

Where does the object pronoun las go?

• Before a conjugated verb: Las imprimo por si…
• Attached to an infinitive: Voy a imprimirlas por si… (also: Las voy a imprimir…)
• Attached to a gerund (with accent): Estoy imprimiéndolas por si…

Does por si need a comma? And is it one word or two?

It’s two words: por si. No comma when the clause comes at the end: Imprimo… por si…. Use a comma if the por si clause comes first: Por si el proyector falla, imprimo…

Is there any difference between por si el proyector falla and por si falla el proyector?

Both are fine. Sujeto + verbo (el proyector falla) vs. verbo + sujeto (falla el proyector) changes the rhythm slightly but not the meaning.

Would se falla be correct for devices?

No. Fallar is intransitive here: el proyector falla. Don’t say se falla. Alternatives by region include se descompone, se daña, no funciona, se echa a perder.

Any regional synonyms for proyector or for “to break down”?

• Projector: proyector (standard), cañón (MX, for data projector), videoproyector, videobeam (CO and elsewhere).
• Break down: se descompone (MX), se daña (Andean region), se echa a perder (widely used), se arruina (some areas).

How would I say this about the past?

Use the preterite in the main clause and imperfect in the por si clause: Imprimí las diapositivas por si el proyector fallaba. For a habitual past: Imprimía… por si… fallaba.

What’s the past participle of imprimir—impreso or imprimido?

Both exist. With haber, both are acceptable: He impreso / he imprimido las diapositivas. As an adjective, impreso is far more common: copias impresas (not usually imprimidas).

Why is si unaccented in por si?

Because it’s the conjunction “if.” Sí with an accent means “yes” or the reflexive intensifier in por sí mismo (“by oneself”). There’s no para si meaning “in case.”

How do I pronounce the ll in falla?

In most of Latin America, ll sounds like English “y”: fa-ya. In the Río de la Plata area (Argentina/Uruguay), it’s often sha/zh: fa-sha/fa-zha.

Could I use para que instead?

Different idea. Para que + subjuntivo expresses purpose: Imprimo las diapositivas para que no haya problemas si el proyector falla. Por si is a precaution, not purpose.

Can I drop the subject yo?

Yes. Spanish is a pro-drop language. Imprimo las diapositivas… is the normal way; Yo imprimo… adds emphasis on “I.”