Si la parrilla sigue fría, pondremos la merluza en el horno y cenaremos dentro de casa.

This is the normal pattern for a real, possible future condition in Spanish:

• si
  • present indicative
• main clause in future, imperative, or sometimes present

So:

• Si la parrilla sigue fría, pondremos la merluza en el horno.

means the condition is seen as realistic.

Spanish does not use the present subjunctive after si in this kind of sentence. So si siga fría would be wrong here.

Compare:

• Si viene, cenamos. = If he comes, we’ll have dinner / we have dinner.
• Si hace frío, nos quedamos en casa. = If it’s cold, we stay home.
• Si la parrilla sigue fría, pondremos la merluza en el horno.

This is different from English, where learners sometimes expect something like if + will. Spanish does not say si seguirá fría here.

Seguir + adjective means to remain / to continue being something.

So:

• está fría = it is cold
• sigue fría = it is still cold / it remains cold

In this sentence, sigue fría suggests that the grill was already cold before, and the speaker is checking whether that situation continues.

That adds an important nuance:

• Si la parrilla está fría... = If the grill is cold...
• Si la parrilla sigue fría... = If the grill is still cold...

So sigue gives the idea of continuation.

Because fría agrees with la parrilla, which is feminine singular.

In Spanish, adjectives must agree in gender and number with the noun they describe:

• el horno está frío
• la parrilla está fría
• las brasas están frías

Here:

• parrilla = feminine singular
• so the adjective must also be feminine singular: fría

Because poner is irregular in the future tense.

Many Spanish future forms are made by adding endings to the infinitive, but some verbs change their stem.
Poner uses the irregular future stem pondr-:

• yo pondré
• tú pondrás
• él/ella pondrá
• nosotros pondremos
• vosotros pondréis
• ellos pondrán

So:

• pondremos = we will put

Other common verbs with similar future irregularities are:

• salir → saldré
• tener → tendré
• venir → vendré
• hacer → haré
• decir → diré

Spanish often uses the definite article more than English does.

Here, la merluza can refer to:

• a specific hake that the speakers already have in mind, or
• hake as the item they are cooking for dinner

In natural Spanish, using the article with food is very common. English often drops the article where Spanish keeps it.

So Spanish can naturally say:

• pondremos la merluza en el horno
• he comprado el pan
• vamos a comer la sopa

Even where English might say just hake, Spanish often prefers la merluza.

Merluza is hake, a white fish that is very common in Spain.

This is a useful cultural note because food vocabulary often reflects what is common in each country. In Spain, merluza is a very normal everyday fish, so the sentence sounds natural and specifically Spanish.

You may also see it in expressions like:

• merluza al horno = baked hake
• filetes de merluza = hake fillets
• merluza a la plancha = grilled hake

Because poner algo en el horno means to put something into the oven.

The preposition en is used after poner to show where something is placed:

• poner la pizza en el horno
• meter el pan en el horno
• dejar la fuente en la mesa

By contrast, al horno is often used as part of a description of how something is cooked:

• merluza al horno = oven-baked hake / baked hake
• pollo al horno = roast chicken / baked chicken

So:

• pondremos la merluza en el horno = we will put the hake in the oven
• haremos merluza al horno = we will make baked hake

Both are correct, but they mean slightly different things.

Because the whole sentence refers to what the speakers will do if that condition is met.

The structure is:

1. condition: Si la parrilla sigue fría
2. result: pondremos... y cenaremos...

Both actions in the result clause are future plans dependent on the condition, so the future tense is very natural:

• pondremos = we will put
• cenaremos = we will have dinner

Spanish could also use other forms depending on style and context, for example:

• Si la parrilla sigue fría, vamos a poner la merluza en el horno y vamos a cenar dentro de casa.

That is also possible, but the simple future sounds neat, clear, and a bit more straightforward here.

Both are possible, but they are not exactly the same.

• en casa = at home
• dentro de casa = inside the house

Dentro de casa emphasizes the contrast with being outside. That matters here because the sentence mentions la parrilla, which suggests outdoor cooking or at least a setting where eating outside might have been the original plan.

So the nuance is something like:

• The grill is cold.
• We will use the oven instead.
• And we will eat inside, not outside.

If you said cenaremos en casa, it would simply mean we’ll eat at home, which is less specific.

Yes, you could. It would still be correct.

The difference is nuance:

• si la parrilla está fría = if the grill is cold
• si la parrilla sigue fría = if the grill is still cold / remains cold

So sigue fría suggests that the speaker expected the grill to heat up, or has been waiting, but it has not happened yet.

That makes sigue fría especially natural in this context.

Because the conditional clause comes first.

In Spanish, when a subordinate clause such as a si clause comes before the main clause, it is normally separated by a comma:

• Si llueve, nos quedamos en casa.
• Si tienes tiempo, llámame.
• Si la parrilla sigue fría, pondremos la merluza en el horno...

If the main clause comes first, the comma is usually not used:

• Pondremos la merluza en el horno si la parrilla sigue fría.

So the comma here is standard punctuation.

Yes. Spanish is fairly flexible, although some versions are more neutral than others.

A very natural alternative is:

• Pondremos la merluza en el horno y cenaremos dentro de casa si la parrilla sigue fría.

This keeps the same meaning, but the emphasis changes slightly:

• starting with Si la parrilla sigue fría... highlights the condition first
• starting with Pondremos... highlights the planned action first

The original version is very natural because it sets up the problem first and then gives the solution.

In this sentence, parrilla most naturally means grill or barbecue grill.

In Spanish, parrilla can refer to different kinds of grilling surfaces depending on context, but here the contrast with el horno and dentro de casa strongly suggests a grill used for cooking, probably outdoors.

So the sentence creates a very natural situation:

• If the grill does not get hot,
• they will switch to the oven,
• and eat inside instead.

That contextual contrast is what makes parrilla easy to interpret here.