Using the Subjunctive Adverb Clauses

Adverbs, remember, answer the question “where,” “why,” “how,” “when,” “to what extent,” “under what circumstances.” We ate before he left. We ate... When? Before he left. We cried because he left. We cried... Why? Because he left. We will cry unless he leaves. We will cry... Under what circumstances? Unless he leaves.

There are certain conjunctions that introduce adverb clauses and REQUIRE the subjunctive: ESCAPA en caso de in case sin que without con tal queprovided that a menos queunless para queso that antes de quebefore

Vamos a salir a menos que nos ayudes. – We’re going to leave unless you help us. Vamos a salir con tal que nos ayudes.– We’re going to leave provided that you help us. Vamos a salir para que nos ayudes. – We’re going to leave so that you’ll help us. Vamos a salir antes de que nos ayudes. – We’re going to leave before you help us. “Sin que” is going to seem kind of strange to you, because we don’t have an equivalent conjunction in English: Vamos a salir sin que nos ayudes. – We’re going to leave without your helping us. As you can see, in English, rather than using a clause, we use a prepositional phrase.

There are some conjunctions, called “time conjunctions,” that SOMETIMES require the subjunctive. Camel oT/HD3 cuandowhen aunqueeven if/although(even though) mientras while en cuantoas soon as luego queas soon as tan pronto comoas soon as hasta queuntil después de queafter de modo que in such a way that de manera que in such a way that If the action in the dependent clause has not yet occurred, it needs the subjunctive: We will eat as soon as you arrive. In the above sentence, you haven’t arrived yet, so “as soon as” must be followed by the subjunctive: Comeremos tan pronto como llegues. He’s going to study after you leave. Va a estudiar despues de que salgas. (You haven’t left yet.) I’m going to read until we eat. Voy a leer hasta que comamos. (We aren’t eating yet.) Nos esconderemos de modo que el no nos vea. (He has not seen us yet)

However, if the action has already occurred, you use the indicative, not the subjunctive: We ate as soon as you arrived. You’ve already arrived, so you use the indicative, not the subjunctive: Comimos tan pronto como llegaste. Similarly... He studied after you left. – Estudió después de que saliste. You already left. You may have concluded that if the verb is in the past tense, you’re going to need the indicative. That isn’t necessarily so. Consider this sentence: I was going to eat as soon as Juan left. During the time frame of this sentence, Juan hadn’t left. You need the subjunctive—imperfect subjunctive: Yo iba a comer tan pronto como Juan saliera.

So, if the action has not yet occurred, you use the subjunctive after the time conjunction. If it has occurred, you use the indicative. But there’s one more consideration: If the action occurs habitually, you use the indicative: We always eat as soon as he arrives. – Siempre comemos tan pronto como llega.... as opposed to the following: We’re going to eat as soon as he arrives. – Vamos a comer tan pronto como llegue. In the red sentence, we’re not talking about a one time occurrence. We’re talking about something that’s a regular, habitual occurrence. In the blue sentence, we’re talking about a particular occasion, and on this particular occasion, his arrival hasn’t happened yet.