Si dejas la plancha encendida, se calentará demasiado.

If you leave the iron on, it will get too hot.

Breakdown of Si dejas la plancha encendida, se calentará demasiado.

• si: if
• demasiado: too
• dejar: to leave
• la plancha: the iron
• encendido: on
• calentarse: to get hot

Questions & Answers about Si dejas la plancha encendida, se calentará demasiado.

What type of conditional is this sentence expressing, and why is it formed with si + present indicative followed by the future tense?

This is the first conditional (real or likely condition). In Spanish, when you talk about a possible present or future situation and its probable consequence, you use:

• Si
  • present indicative (here si dejas)
• main clause in future indicative (here se calentará)

Why is dejar used with encendida instead of using an infinitive like “dejas encender”?

Spanish has a “dejar + object + past participle” structure that means “to leave something in a certain state.” In this case:

• dejas (you leave)
• la plancha (the iron)
• encendida (turned on)

So dejar la plancha encendida = “to leave the iron turned on.”

What does encendida mean here, and why does it end in “-a”?

Encendida is the past participle of encender used as an adjective meaning “turned on.” It agrees in gender and number with la plancha (feminine singular), so we use -a.

What role does the se play in se calentará?

This se is a pronominal or “medio” se that makes calentar intransitive:

• calentar alone = “to heat (something)”
• se calentar = “to get hot”

So se calentará = “it will get hot.”

Why is the verb calentará in the future tense, not the present or subjunctive?

In a first conditional, Spanish uses the future indicative in the main clause to express a consequence that is likely to happen if the condition is met. It also adds a sense of warning: “it will get too hot.”

Why is demasiado used instead of muy?

• demasiado modifies verbs/adjectives as “too much” (e.g. “too hot”).
• muy only modifies adjectives/adverbs to mean “very.”
  Here you want “too hot,” so you need demasiado.

Could you say se va a calentar instead of se calentará?

Yes. The periphrastic future (ir a + infinitive) is very common in speech:

• se calentará (will get hot)
• se va a calentar (is going to get hot)

Both express future meaning here.

How would you change this sentence to address someone formally (using usted)?

Use the third-person singular form and optionally add usted:
Si usted deja la plancha encendida, se calentará demasiado.
Here deja corresponds to usted, and se calentará stays the same.