Spanish Subjunctive: Doubt, Disbelief, and Denial

Vocabulary and grammar rules for using the subjunctive versus the indicative with expressions of doubt, disbelief, and certainty in Spanish.

dudar

To doubt; an expression that triggers the subjunctive in a subordinate clause when there is a change of subject.

negar (e:ie)

To deny; an expression of disbelief or denial that requires the subjunctive in the subordinate clause.

no creer

Not to believe; unlike 'creer', this expression implies doubt and is followed by the subjunctive.

no estar seguro/a (de)

Not to be sure (of); an expression of uncertainty that triggers the subjunctive.

no es cierto / no es verdad

It's not true or it's not certain; expressions of negation and disbelief that trigger the subjunctive.

es improbable

It's improbable; an expression of doubt that triggers the subjunctive.

(no) es posible / (no) es probable

It's (not) possible/probable; in Spanish, these imply inherent uncertainty and always trigger the subjunctive in the subordinate clause.

es imposible

It's impossible; an expression of denial that triggers the subjunctive.

Quizás / Tal vez

Perhaps; adverbs that imply uncertain possibility and are usually followed by the subjunctive.

es cierto / es verdad

It's true; expressions of certainty that trigger the indicative mood in the subordinate clause.

es obvio / es seguro

It's obvious or it's certain; expressions of certainty used with the indicative mood.

no cabe duda de / no hay duda de

There is no doubt; expressions of certainty that trigger the indicative mood.

no dudar / no negar (e:ie)

Not to doubt or not to deny; expressions of certainty that are followed by the indicative.

creer

To believe; an expression of belief or certainty that is followed by the indicative.

Infinitive rule for doubt

The infinitive is used after expressions of uncertainty, doubt, or denial when there is no change of subject (e.g., 'Dudo llegar temprano').