The subjunctive isn’t a tense: present, past, or future. It is a mood (or mode), because it indicates how the speaker feels about or perceives a situation rather than when an action occurred. The subjunctive expresses unreal, hypothetical, theoretical, imaginary, uncorroborated, or unconfirmed conditions or situations. These expressions come from the speaker’s doubts, emotions, wishes, wants, needs, desires, feelings, speculations, or suppositions.

Forming the Simple Present subjunctive

Verbs ending in –ar.

Hablar (to speak)

Yo habl-e
Tú habl-es
Él habl-e
Nosotros habl-emos
Vosotros habl-éis
Ellos habl-en

Verbs ending in –er

Comprender (to understand)

Yo comprend-a
Tú comprend-as
Él comprend-a
Nosotros comprend-amos
Vosotros comprend-áis
Ellos comprend-an

Verbs ending in –ir

Escribir (to write)

Yo escrib-a
Tú escrib-as
Él escrib-a
Nosotros escrib-amos
Vosotros escrib-áis
Ellos escrib-an

Uses

1. The subjunctive is used in sentences that express doubt, probability. It is often used after adverbs like quizás, tal vez (maybe), acaso (in case), posiblemente (possibly) and probablemente (probably).

Quizá vayamos a lo de Juan esta noche. (Maybe we’ll go over to Juan’s tonight.)
Tal vez compren una casa en el campo. (Maybe they’ll buy a country house.)

Exception: with a lo mejor, we must use the indicative.

A lo mejor vienen más tarde. (They’ll probably come later.)

2. Expressing wishes.

¡Que disfrutes el paseo! – (May you) Enjoy your tour!
¡Que te vaya bárbaro ese viaje! – (May you) Have a good time on this trip!
¡Ojalá se recupere pronto! – I wish he gets better soon!

3. Reduplicative sentences.

Pase lo que pase, estaré a tu lado. – Whatever happens, I’ll be by your side.
Diga lo que diga, no le hagas caso. – Whatever he says, don’t pay any attention to him.
Venga quien venga, no recibiré a nadie. – I won’t see anyone, whoever it is.

4. With impersonal expressions.

It is absurd that – es absurdo que
It is advisable that – conviene que
It is amazing that – es asombroso que
It is amusing that – es divertido que
It is bad that – es malo que
It is better that – es mejor que, má vale que
It is curious that – es curioso que
It is difficult that – es difícil que
It is doubtful that – es dudoso que
It is easy that – es fácil que
It is enough that – es suficiente que, basta que
It is essential that – es esencial que

5. Expressing time condition with cuando (when), tan pronto como, en el momento en que, así que, en cuanto (as soon as).

En cuanto recibamos la herencia, nos compraremos una casa nueva. (As soon as we get the inheritance, we’ll buy a new house.)
Me cambio de empleo, tan pronto como encuentre uno mejor que me pague más. (I’ll change my job as soon as I find a better one that pays more.)

To be continued…