The subjunctive mood is used primarily in dependent clauses. Of course, the subjunctive mood is used on other occasions as well, depending on the type of clause, the action/state involved, and its relationship to other elements in the sentences such as the governing verb.
Dependent Clauses (view lesson here)
The subjunctive is usually used in dependent clauses introduced by que or another subordinating conjunction.
Wishes, Hopes, and Fantasies (view lesson here)
esperar, ojalá que, etc.
Yo espero que a Juan le guste la música.
I hope that John likes the music.
Requests, Suggestions, Intentions (view lesson here)
Verbs of influence are used to express influence over actions that the subject would or would not like somebody else to do, but cannot directly control.
querer, decir, pedir, insistir, preferir, recomendar, etc.
El profesor quiere que tú hagas la tarea.
The teacher wants you to do the homework.
Express Doubt, Possibilities, Uncertainties (view lesson here)
When the main clause expresses less than 100% certainty about the truth of a que-clause, the verb is in the subjunctive.
pensar que, quizás, tal vez, no saber, no creer, dudar, negar, es posible, es probable, etc.
Es probable que el tren llegue con retraso.
The train will probably arrive late.
Marcos duda que el jardinero trabaje hoy.
Marcos doubts that the gardener will work today.
Es posible que vayamos a la playa mañana.
It's possible that we'll go to the beach tomorrow.
Unrealized or Hypothetical Events, Situations, or Entities (view lesson here)
cuando, en cuanto, mientras, hasta, etc.
Le hablaré cuando vuelva.
I will speak to him when he returns.
Llámame en cuanto llegues.
Call me as soon as you get there.
Expressing Judgement or Emotion to an Event (view lesson here)
The subjunctive mood is used in a subordinate clause following the expression of an emotion or judgement.
sentir, alegrarse de, es bueno, es malo, es una lástima, es increíble....
Me alegro de que hayas venido.
I am glad that you have come.
Necessity or Obligation (view lesson here)
es necesario, es preciso, hace falta que, etc.
Es necesario que usted coma.
It is necessary that you eat.
Es preciso que trabaje.
It is necessary that you work.
Commands (view lesson here)
Use the Subjunctive in all direct commands for usted, ustedes, and nosotros and in negative commands for tú and vosotros.
Tú
Camina más despacio. - Walk slower. - Indicative
No camines tan rápido. - Don't walk so fast. - Subjunctive
Usted, Ustedes
Díga(n)me mentiras. - Tell me lies. - Subjunctive
No me diga(n) la verdad. - Don't tell me the truth. - Subjunctive
Vosotros
Comed con nostros. - Eat with us. - Indicative
No comáis los frijoles. - Don't eat the beans. - Subjunctive
Nosotros
Comamos. - Let's eat. - Subjunctive
No comamos. - Let's not eat. - Subjunctive
You can conjugate any verb in the Spanish language provided you know the infinitive.
Start with the first person singular (yo-form) of the present indicative.
1. If this form does not end in an -o, the verb is irregular in the present subjunctive; memorize the forms.
Yo-form - Infinitive Present Subjunctive Forms
yo tú Ud./él/-la nosotros vosotros Uds.
soy ser: sea seas sea seamos seáis sean
estoy estar: esté estés esté estemos estéis estén
voy ir: vaya vayas vaya vayamos vayáis vayan
doy dar: dé des dé demos deis den
sé saber: sepa sepas sepa sepamos sepáis sepan
Note: the endings for the present subjunctive for all other verbs are:
Endings for -ar verbs
-e - emos - es - eis - e - en
Endings for -er and -ir verbs
-a - amos - as - áis - a - an
(These endings are or the most part the “opposite” conjugation endings of the present indicative.)
2. If the stem of the yo-form is exactly the same as the stem of the infinitive, the verb is regular; use this stem and attach the appropriate endings.
Yo-form, Infin- Present subjunctive forms
yo tú Ud./él/-la nosotros vosotros Uds.
hablo hablar: hable hables hable hablemos habléis hablen
como comer: coma comas coma comamos comáis coman
vivo vivir: viva vivas viva vivamos viváis vivan
3. If the stem of the yo-form shows a stem change when compared to the stem of the infinitive (e > ie, o > ue, or u > ue) and it's an -ar or -er verb, the stem will undergo the same changes as in the present indicative (in all forms except for nosotros and vosotros); substitute the subjunctive endings for the indicative ones:
Yo-form, Infin- Present subjunctive forms
yo tú Ud./él/-la nosotros vosotros Uds.
vuelvo volver: vuelva vuelvas vuelva volvamos volváis vuelvan
4. If the stem of yo-form, when compared to that of the infinitive, shows that an -ir stem-changing verb is involved, all forms of the present subjunctive will have stem changes: the same ones as in the present indicative (e > ie, o > ue, and e > i), plus special changes in the nosotros and vosotros forms (e > i, o > u):
Yo-form, Infin- Present subjunctive forms
yo tú Ud. nosotros vosotros Uds.
siento sentir: sienta sientas sienta sintamos sintáis sientan
duermo dormir: duerma duermas duerma durmamos durmáis duerman
pido pedir: pida pidas pida pidamos pidáis pidan
5. We are left with a yo form stem which is NOT the same as the one for the infinitive and which is NOT a stem-changing verb: use this stem for all forms of the present subjunctive:
Yo-form, Infin- Present subjunctive forms
yo tú Ud. nosotros vosotros Uds.
conozco conocer: conozca conozcas conozca conozcamos conozcáis conozcan
tengo tener: tenga tengas tenga tengamos tengáis tengan
Some of the verbs in this category:
caer (caigo) salir (salgo)
conocer (conozco) seguir (sigo)
decir (digo) valer (valgo)
hacer (hago) venir (vengo)
poner (pongo)
Remember that compounds based on these verbs also have special yo-forms, e.g., reconocer, deshacer, proponer, conseguir, etc.
6. Remember that spelling (or orthographic) changes take place in the subjunctive forms of some verbs to maintain the pronunciation of the consonant sound preceding the infinitive:
Infinitive ending Subj. ending Examples
-car > -que
-gar > -gue
-zar > -ce
-cer or -cir > -za
-ger or -gir > -ja
Yo-form, Infin- Present subjunctive forms
yo tú Ud. nosotros vosotros Uds.
busco buscar: busque busques busque busquemos busquéis busquen
pago pagar: pague pagues pague paguemos paguéis paguen
empiezo empezar: empiece empieces empiece empecemos empecéis empiecen
ejerzo ejercer: ejerza ejerzas ejerza ejerzamos ejerzáis ejerzan
cojo coger: coja cojas coja cojamos cojáis cojan