Spanish/Tenses/Subjunctive/Simple
The present subjunctive in Spanish is formed by adding the following endings to the stems of verbs: -ar: -e, -es, -e, -emos,- éis, -en -er/-ir: -a, -as, -a, -amos, -áis, -an
Verbs that are stem changing/ boot verbs in the present indicative will do the same in the present subjunctive. If a verb has an irregular yo form in the present indicative that is the base form for the present subjunctive; hence tener, tengo, becomes: tenga, tengas, tenga, etc., or oír, oigo, becomes: oiga, oigas, oiga, etc.
Verbs that end in –uir, like huir, which have a ‘y’ between stem and ending in the boot (all forms but nosotros and vosotros) in the present indicative function as yo irregulars: all six forms in the present subjunctive have the ‘y’: huya, huyas, huya, huyamos, huyáis, huyan.
For phonetic reasons there are various spell changes. The –car, -gar, -zar, -guar yo spell changes in the preterit occur in all six forms of the present subjunctive. Sacar: saque, saques, saque, etc. Llegar: llegue, llegues, llegue, etc. Lanzar: lance, lances, lance, etc. Averiguar: averigüe, averigües, averigüe, etc. Also yo spell changes from the present indicative will occur in all six forms in the present subjunctive for: -ger/gir, consonent+-zar, -guir. Escoger: escoja, escojas, escoja, etc. Vencer: venza, venzas, venza, etc. Seguir: siga, sigas, siga, etc.
-ir stem changing verbs will have a change in the nosotros and vosotros forms, with the ‘o’ in the stem becoming a ‘u’ or the ‘e’ becoming an ‘i’. Morir: muera, mueras, muera, muramos, muráis, mueran. Sentir: sienta, sientas, sienta, sintamos, sintáis, sientan.
There are six irregular verbs in the present subjunctive: Ser: sea, seas, sea, seamos, seáis, sean Ir: vaya, vayas, vaya, vayamos, vayáis, vayan Saber: sepa, sepas, sepa, sepamos, sepáis, sepan Haber: haya, hayas, haya, hayamos, hayáis, hayan Estar: esté, estés, esté, estemos, estéis, estén Dar: dé, des, dé, demos, deis, den
The imperfect subjunctive in Spanish is formed by adding the following endings to the third person plural of the preterit after removing the ‘-ron’ -ra, -ras, -ra, ’-ramos, -rais, -ran
Hence hablar, hablaron, becomes: hablara, hablaras, hablara, habláramos, hablarais, hablaran
Or vivir, vivieron, becomes: viviera, vivieras, viviera, viviéramos, vivierais, vivieran An alternative, less used, set of endings is also available: -se, -ses, -se, ’-semos, -seis, -sen
The future subjunctive (not commonly used but an accepted form), like the imperfect subjunctive, is formed using the third person plural of the preterit after removing the ‘-ron’. The endings are: -re, -res, -re, ’-remos, -reis, -ren