If__ then__.: Using the Past Subjunctive + Conditional

A combination of the conditional mood and the past subjunctive tense is used when talking about hypothetical situations that the speaker does not expect to take place.

The if part of the statement is in the past subjunctive tense, while the result is in the conditional mood. Watch out! It is common for English speakers to use -- incorrectly -- would in both parts of the sentence, so if you can't tell which part is which, try adding in the optional then to determine where the conditional goes:

• Podríamos ir a la playa si no lloviera.
  We could go to the beach if it weren't raining.
  
  Si no lloviera, podríamos ir a la playa.
  If it weren't raining, (then) we could go to the beach.

Here's the formula:

• If + past subjunctive verb..., (then +) conditional verb

Note that both the conditional and the subjunctive can be used in the simple past:

• Podríamos pasar el día de Acción de Gracias en Los Ángeles si reserváramos nuestro vuelo cuanto antes.
  We could spend Thanksgiving in Los Angeles if we booked our flight right away.

and the compound past:

• Podríamos haber pasado el día de Accón de Gracias en Los Ángeles si hubiéramos reservado nuestro vuelo cuanto antes.
  We could have spent Thanksgiving in Los Angeles if we had booked our flight right away.
  

The Simple Past

There are two different forms for the past subjunctive, and both are equally correct for use in the if clause, but the form most commonly used all over the Spanish-speaking world is the imperfect subjuctive.

It is important that you be familiar with the preterite indicative conjugations, because the imperfect subjunctive is formed from the ellos form of the preterite indicative. Even the irregular forms come directly from the ipreterite indicative third person plural form. If you aren't able to conjugate the preterite indicative, now is the time to master this very important verb tense.

Once you have learned and can use this preterite form, conjugating the imperfect subjunctive is actually quite easy.

Let's take our -ar model verb hablar. The preterite indicative third person plural (ellos) form is:

• hablaron

To conjugate hablar in the imperfect subjunctive, take hablaron and change the -o- to an -a-, which gives us hablaran, the base form for the imperfect subjunctive conjugation of this verb:

HABLAR
yo	hablara
tú	hablaras
él/ella, Ud.	hablaran
nosotros	habláramos
vosotros	hablaráis
ellos/ellas, Uds.	hablaran

The same process is applied to -er and -ir verbs:

COMER  The preterite third person plural (ellos) form is comieron. We change the final -o- to an -a-, which gives us comieran, the base form for the imperfect subjunctive:

COMER
yo	comiera
tú	comieras
él/ella, Ud.	comieran
nosotros	comiéramos
vosotros	comieráis
ellos/ellas, Uds.	comieran

VIVIR  The preterite third person plural (ellos) is vivieron. Changing the -o- to -a- gives us vivieran, the base form of the imperfect subjunctive:

VIVIR
yo	viviera
tú	vivieras
él/ella, Ud.	vivieran
nosotros	viviéramos
vosotros	vivieráis
ellos/ellas, Uds.	vivieran

Note that, just as in the present subjunctive, the yo and él/ella, Ud. forms are identical, so once again, in order to avoid ambiguity, the subject pronoun may have to be used.


Although the subjunctive is extemely important in Spanish, its use in English goes unnoticed because in English most of the subjunctive forms coincide with the indicative forms.  An exception to this are the  I and he/she/it forms of the English verb to be.

Compare the following sentences:

• Estaba enfermo, así que no fui al trabajo.
  I was sick, so I didn't go to work.  (indicative)
  
  Si estuviera enfermo, no iría al trabajo.
  If I were sick, I wouldn't go to work.  (subjunctive)

It's clear that the first, indicative, sentences are describing a reality, while the second, subjunctive, sentences are describing a hypothetical situation, and it is the English subjunctive were and conditional would that tell us so.


Using the English subjunctive were can help us to translate and understand the Spanish subjunctive:

• yo hablara -- I spoke, I were speaking
  tú comieras -- you ate, you were eating
  él/ella/Ud. viviera -- he/she/you (formal) were living, etc.
  

• Si yo hablara francés, el camarero me entendería.
  If I spoke (were speaking) French, the waiter would understand me.
  
  Si comieras ensalada a diario, estarías más delgada.
  If you ate (were eating) salad daily, you would be slimmer.
  
  Si Ud. viviera en en centro, no tendrías que conducir al trabajo.
  If you lived (were living) in the city centre, you wouldn't have to drive to work

Another conjugation option is to use the preterite subjunctive instead of the imperfect subjunctive in this kind of phrase, a practice very common in Spain, but limited in Latin America.

The preterite subjunctive conjugation can be formed by substituting -se for the -ra of the imperfect conjugation:

• yo hablase, comiese, viviese
  tú hablases, comieses, vivieses
  él/ella/Ud.  hablase, comiese, viviese
  nosotros hablásemos, comiésemos, viviésemos
  vosotros hablaséis, comieséis, vivieséis
  ellos/ellas/Uds. hablasen, comiesen, viviesen
  

The Compound Past

To form this type of hypothetical sentence in the compound past, we follow the same procedure as for the indicative, except we conjugate haber+ participle  in the imperfect or preterite subjunctive in the if clause and use haber + participle in the conditional in the resultant clause.

Here's the formula:

• If + past subjunctive form of haber + participle..., (then +) conditional form of haber + participle...

• Si hubiera sabido llegar al aeropuerto, no habría tomado un taxi.
  If I had known how to get to the airport, I would not have taken a taxi.
  
  Habría vuelto antes si hubiese sabido que iba a haber una huelga.
  I would have returned earlier if I had known there was going to be a strike.

Here is haber conjugated in the imperfect subjunctive, the preterite subjunctive and the conditional:

yo	hubiera	hubiese	habría
tú	hubieras	hubieses	habrías
él/ella/Ud.	hubiera	hubiese	habría
nosotros	hubiéramos	hubiésemos	habríamos
vosotros	hubieréis	hubieséis	habríais
ellos/ellas/Uds.	hubieran	hubiesen	habrían

A Final Word

Finally, there are other verb tense and mood conjugation combinations that are commonly used to talk about the same kind of hypothetical situations as in the sentences we have studied above. Below are sentences structured according to the rules we have studied, compared with examples of some of the other ways of expressing the same concept using different tenses and moods.

It isn't necessary to master the use of these alternative models, but because the subjunctive plays such an important role in communication in Spanish, it is crucial that you be able to recognize the "hypothetical" nature of these statements, except the first example, which is in the indicative.

• Si estudio bien, aprenderé mucho español.(present indicative/future indicative)
  If I study well, I'll learn a lot of Spanish.
  
  Si (yo) estudiara bien, aprendería mucho español.
  (imperfect subjunctive/conditional)
  If I studied well, I'd learn a lot of Spanish.
  
  Si (yo) estudiase bien, aprendería mucho español.
  (preterite subjunctive/conditional)
  If I studied well, I'd learn a lot of Spanish.
  
  Si (yo) estudiase bien, aprendiera mucho español.
  (preterite subjunctive/imperfect subjunctive)
  If I studied well, I'd learn a lot of Spanish.
  
  Si (yo) estudiara bien, aprendiera mucho español.
  (imperfect subjunctive/imperfect subjunctive)
  If I studied well, I'd learn a lot of Spanish.

Note that, just as in the present subjunctive tense and the conditional mood, the yo and él/ella, Ud. forms are identical, so in order to avoid ambiguity, the subject pronoun may have to be used if the sentence's subject is not clear from the context.