1. In Spanish, adverbial clauses are commonly introduced by conjunctions
In Spanish, adverbial clauses are commonly introduced by conjunctions. Certain conjunctions require the subjunctive, while others can be followed by the subjunctive or the indicative, depending on the context in which they are used.
© by Vista Higher Learning, Inc. All rights reserved.

2. An adverbial clause (cláusula adverbial) is one that modifies or describes verbs, adjectives, or other adverbs. It describes how, why, when, or where an action takes place.
© by Vista Higher Learning, Inc. All rights reserved.

3. MUST HAVE A CHANGE OF SUBJECT
Conjunctions that require the subjunctive
Certain conjunctions are always followed by the subjunctive because they introduce actions or states that are uncertain or have not yet happened.
MUST HAVE A CHANGE OF SUBJECT
These conjunctions commonly express purpose, condition, or intent.
Se acabará el petróleo en pocos años
a menos que
busquemos energías alternativas.
MAIN CLAUSE
CONNECTOR
SUBORDINATE CLAUSE
Petroleum will run out in a few years
unless
we look for alternative energy sources.
© by Vista Higher Learning, Inc. All rights reserved.

4. ____________________________________haya ______________________
El gobierno se prepara en caso de que ________ una gran sequía el verano que viene.
The government is getting ready in case there is a big drought in the coming summer.
© by Vista Higher Learning, Inc. All rights reserved.

5. Note that the connector que is not necessary in this case.
If there is no change of subject in the sentence, a subordinate clause is not necessary. Instead, the prepositions antes de, con tal de, en caso de, para, and sin can be used, followed by the infinitive.
Note that the connector que is not necessary in this case.
Las organizaciones ecologistas trabajan para __________los arrecifes de coral.
Environmental organizations work to protect coral reefs.
____________________________________proteger
© by Vista Higher Learning, Inc. All rights reserved.

6. estemos Conjunctions followed by the subjunctive or the indicative
If the action in the main clause has not yet occurred, then the subjunctive is used after conjunctions of time or concession.
estemos
La excursión no saldrá hasta que ________________ todos.
The excursion will not leave until we all are here.
© by Vista Higher Learning, Inc. All rights reserved.

7. If the action in the main clause has already happened, or happens habitually, then the indicative is used in the adverbial clause.
paró
Tan pronto como ______ de llover, Matías ______ a jugar al parque.
As soon as the rain stopped, Matías went out to play in the park.
salió
© by Vista Higher Learning, Inc. All rights reserved.

8. Aunque me digan que es inofensivo, no me acercaré al perro.
1. We will set the bird free as soon as the veterinarian tells us it can fly.
Dejaremos libre al pájaro en cuanto el veterinario nos diga que puede volar.
2. Even if they tell me he’s harmless, I’m not going near the dog.
Aunque me digan que es inofensivo, no me acercaré al perro.
3. When Pedro goes hunting, he will watch out for the poisonous snakes.
Cuando Pedro vaya a cazar, tendrá cuidado con las serpientes venenosas.
© by Vista Higher Learning, Inc. All rights reserved.

9. A menos que haga mal tiempo, iremos a la montaña el próximo miércoles.
4. Unless the weather is (makes) bad, we will go to the mountains next Wednesday.
A menos que haga mal tiempo, iremos a la montaña el próximo miércoles.
5. We should protect wild animals before they become extinct.
Debemos proteger a los animales salvajes antes de que se extingan.
6. You need to get permission before feeding (giving to them) the monkeys of the zoo.
Necesitas permiso antes de darles de comer a los monos del zoológico.
© by Vista Higher Learning, Inc. All rights reserved.

10. En cuanto terminó la tarea, la nota subió.
7. My father and I always have fun when we go to the river.
Mi padre y yo siempre nos divertimos cuando vamos al río.
8. As soon as he finished his homework, his grade went up.
En cuanto terminó la tarea, la nota subió.
9. Until we protect the oceans, we will always be in danger of famine.
Hasta que protejamos los océanos, siempre estaremos en peligro de hambruna.
© by Vista Higher Learning, Inc. All rights reserved.

11. Tan pronto como llueva, el problema de la sequía se reducirá.
10. When the forests disappear, many species are lost.
Cuando los bosques desaparecen, muchas especies se pierden.
11. As soon as it rains, the problem of drought will be reduced.
Tan pronto como llueva, el problema de la sequía se reducirá.
12. The natural resources will run out (be used up) un less everyone (we) conserve them.
Los recursos naturales se agotarán a menos que todo el mundo los conservemos.
© by Vista Higher Learning, Inc. All rights reserved.