​Conjunctions:
Words or phrases that connect other words and clauses in sentences.

Certain conjunctions:
Introduce adverbial clauses:
How,
Why,
When, and
Where
an event takes place.

​Ejemplo:

​Vamos a visitar al abuelo

antes de que

regrese a Washington.

We are going to visit grandpa

before

he returns to Washington.

The subjunctive is used with certain conjunctions to express:

• a hypothetical situation

• uncertainty as to whether an action or event will take place

• a condition that may or may not be fulfilled

​Ejemplo:
Voy al supermercado para que tengas algo de comer.
I'm going to the store so that you'll have something to eat.

​List of conjunctions that ALWAYS require the subjunctive:

• a menos que - unless

• antes (de) que - before

• con tal (de) que - provided that

• en caso (de) que - in case (that)

• para que - so that

• sin que - without

​****ATENCIÓN:
The infinitive (not the subjunctive) is used after the prepositions:
-antes de Te llamo antes de salir.
-para
-sin

​a menos que...

​No voy a la fiesta a menos que tú vayas también

​en caso de que...

​Voy a hacer mi tarea hoy en caso de que vayamos a la playa mañana.

​antes de que...

​Necesitamos hacer algo por los animales antes de que se extingan.

​CONJUNCTIONS WITH
SUBJUNCTIVE OR INDICATIVE

​-cuando - when
-después de que - after
-en cuanto - as soon as
-hasta que - until
-tan pronto como - as soon as

​The subjunctive is used with the previous conjunctions if:

the main clause expresses a future action or command.

​Van a contaminar los ríos cuando construyan nuevos edificios.
They are going to pollute the rivers when they build new buildings.

​The indicative is used with the previous conjunctions if:

the main clause expresses an action that habitually happens, or that happened in the past.

​Contaminaron el río cuando construyeron ese edificio.
They polluted the river when they built that building.