Use of Subjunctive

Commands

Use subjunctive forms in

all commands for usted(es) and nosotros
negative commands for tú and vosotros
Affirmative Commands Negative Commands
Póngalo aquí. No lo ponga aquí.
Sentémonos ahora. No nos sentemos todavía.
Dímelo. No me lo digas.
Dadles el dinero. No les déis el dinero.

Subordinate Clauses

Elsewhere, the subjunctive is most frequent in subordinate clauses introduced by que or another subordinating conjunction, but not all que-clauses take the subjunctive. All of these clauses fulfill one of two conditions: they either describe a potential or hypothetical situation, or else they reflect the subject's subjective or emotional reaction to a situation. Usually the main clause contains elements which condition the choice of the subjunctive. (Surprisingly, clauses introduced by the conjunction si 'if', which typically expresses a hypothetical condition, do not require the subjunctive.)

Potential Events

Wishes

esperar, ojalá que... Espero que regrese pronto. I hope she comes back soon.
Requests / Suggestions / Intentions
decir, pedir, insistir en, preferir,
recomendar, sugerir, mandar, para que... El profesor quiere que aprendamos el subjuntivo. The professor wants us to learn the subjunctive.

Necessity / Obligation

es necesario, hace falta que... Es necesario que lea el libro de texto antes de ir a clase. It's necessary for you to read the textbook before going to class.

Possibilities, Uncertainties

Es posible / probable / dudoso...; no creer, dudar, negar... Es probable que salgan bien en el examen. It's likely you'll do well on the test.
Duda que puedas terminar a tiempo. He doubts you'll be able to finish on time.

Unrealized or Hypothetical Events, Situations, or Entities

cuando, en cuanto, mientras, hasta...
with future (but not past or habitual) actions;
antes de que, a menos que, con tal que, sin que (always);
aunque, relative clauses
(only hypothetical , not existing situations). Todo estará perfecto cuando Ud. vuelva a casa.
Quiero leer esta revista mientras mires tus telenovelas.

Aunque la mona se vista de seda, mona queda.
Everything will be fine when you get home.
I want to read this magazine while you watch your soaps.

Even if the monkey gets dressed up in silk, she's still a monkey.
(=You can't make a silk purse out of a sow's ear.)

Subjective Reaction

Personal Reaction of Speaker or Subject of Sentence to an actual Event or Situation

sentir, alegrarse de,
es bueno / malo / lástima / increíble... ¡Qué suerte que se hayan encontrado después de tantos años! How lucky for you to have found each other after so many years!
Me alegro de que Uds. puedan ir a la fiesta I am glad that you can go to the party.

Details (Fill in your own details and additional examples)

Influencing Others
Two clauses, Same subject: infinitive
Change of subject: que + subjunctive
Necessity or Obligation
(No) es necesario / preciso / imprescindible que...

Subjective Reaction

Unrealized Events
Past / Habitual (Indicative) Future (Subjunctive)

Nothing But The Truth

When the main clause expresses less than 100% certainty about the truth of a que-clause, the verb is in the subjunctive.

Certain (indicative) Not 100% Certain (subjunctive)

saber / creer / pensar que
no dudar / no negar que
es verdad / cierto / seguro que
no saber / no creer / no pensar que
dudar / negar que
no es verdad / cierto que
(no) es (im)posible / probable que
quizás / tal vez