Breakdown of Organizaremos el picnic, a menos que llueva.
llover
to rain
organizar
to organize
el picnic
picnic
a menos que
unless
Questions & Answers about Organizaremos el picnic, a menos que llueva.
Why is llueva in the subjunctive here?
The phrase a menos que (unless) always triggers the subjunctive. This is because it introduces a condition or exception that hasn't happened yet and might not happen, making the event hypothetical.
Since the main verb organizaremos is in the future tense, why isn't the verb for 'rains' also in a future tense?
In Spanish, the present subjunctive is used to talk about future hypothetical events after triggers like a menos que. The future subjunctive does exist, but it is obsolete in modern everyday Spanish, so the present subjunctive (llueva) steps in to cover future meanings.
Can I use a no ser que or salvo que instead of a menos que in this sentence?
Yes, you can! A no ser que and salvo que both mean 'unless' and they also require the subjunctive. You could say Organizaremos el picnic, salvo que llueva or Organizaremos el picnic, a no ser que llueva with exactly the same meaning.
What is the infinitive of llueva, and why does it have a 'ue' in it?
The infinitive is llover (to rain). It is an O-to-UE stem-changing verb. Just like in the normal present tense (llueve), that same vowel change carries over to the present subjunctive, giving us llueva.