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Spanish 3 Unit 3: Subjunctive with Doubt and Impersonal Expressions

This unit shows how doubt, denial, disbelief and impersonal expressions of opinion trigger the subjunctive, while expressions of certainty keep the indicative. It also covers quizás and tal vez and the present perfect subjunctive.

Covers: Doubt and denial, Certainty and the indicative, Negation and mood changes, Impersonal expressions, Quizás, tal vez and a lo mejor, Present perfect subjunctive

Study guide

When a speaker doubts or denies something, the action in the que clause is not presented as real, so it goes into the subjunctive. Common triggers are dudar que, no creer que, no pensar que, no estar seguro de que, negar que, and no es cierto que or no es verdad que. Compare Dudo que Pedro venga (I doubt Pedro is coming) with No dudo que Pedro viene (I don't doubt he's coming). Removing the doubt turns the clause back into a fact, so the indicative returns. Learning to watch for no in the main clause is one of the most tested skills in this unit.

Expressions of certainty and belief take the indicative in affirmative sentences: creer que, pensar que, estar seguro de que, es cierto que, es verdad que, es obvio que, es evidente que, no hay duda de que. Creo que tienes razón uses the indicative because the speaker presents it as true. When these are negated, they usually become triggers: No creo que tengas razón. In questions, either mood is possible: ¿Crees que viene? suggests the speaker expects yes, while ¿Crees que venga? signals more doubt. Class tests normally focus on the affirmative and negative pattern.

Impersonal expressions with es + adjective + que state an opinion, judgment, necessity or possibility rather than a fact, so they trigger the subjunctive when they have a specific subject: es importante que, es necesario que, es mejor que, es posible que, es imposible que, es probable que, es raro que, es bueno que, es una lástima que, and es urgente que. For example, Es necesario que tú practiques. If there is no specific subject, use the infinitive: Es necesario practicar (it is necessary to practice). Students often add que when no new subject appears, which is an error.

Quizás, quizá and tal vez (perhaps) work differently from the other triggers because they are adverbs, not verbs with que. They take the subjunctive when the speaker feels real doubt and the indicative when the speaker leans toward belief: Tal vez llueva (doubtful) or Tal vez llueve (more likely). A lo mejor, also meaning maybe, normally takes the indicative: A lo mejor viene mañana. This flexibility means test questions usually ask which sentence is possible rather than which one is required.

When the doubted or judged action is already completed, use the present perfect subjunctive: haya, hayas, haya, hayamos, hayáis, hayan + past participle. Dudo que ellos hayan terminado means I doubt they have finished. Es posible que ya haya llegado means It's possible he has already arrived. Compare Dudo que termine (I doubt he will finish or is finishing) with Dudo que haya terminado (I doubt he has finished). The helper haya comes from haber, a DISHES verb, and participles follow the same rules as in the present perfect indicative (hecho, dicho, escrito, puesto, vuelto).

Key ideas

• Doubt and denial (dudar que, negar que, no creer que) trigger the subjunctive.
• Certainty (creer que, estar seguro de que, es verdad que) takes the indicative when affirmative.
• Negating certainty usually produces the subjunctive; negating doubt (no dudar que) produces the indicative.
• Impersonal es + adjective + que expressions of opinion, necessity or possibility take the subjunctive.
• Impersonal expressions with no specific subject use the infinitive.
• Quizás and tal vez can take either mood depending on the speaker's degree of doubt; a lo mejor takes the indicative.
• The present perfect subjunctive (haya + participle) expresses doubt or judgment about completed actions.

Formulas and rules

Common mistakes

• Using the subjunctive after creo que or es verdad que in affirmative sentences.
• Using the indicative after no creo que or no es cierto que.
• Using the subjunctive after no dudo que, which removes the doubt.
• Adding que + subjunctive after an impersonal expression when no specific subject exists.
• Treating es obvio que and es evidente que like opinions; they state certainty and take the indicative.

Before the test, make sure you can

• Identify expressions of doubt and denial that trigger the subjunctive.
• Explain how negation changes the mood after creer, pensar, dudar and estar seguro.
• Classify impersonal expressions as opinion or certainty and choose the mood.
• Choose between an infinitive and que + subjunctive after impersonal expressions.
• Use quizás, tal vez and a lo mejor with an appropriate mood.
• Form and use the present perfect subjunctive.
• Correct mood errors in sentences with certainty and doubt.

Words to know

dudar

to doubt

negar (ie)

to deny

la duda

doubt

dudoso/a

doubtful

cierto/a

true, certain

seguro/a

sure

evidente

evident

obvio/a

obvious

claro

clear

es imprescindible

it is essential

es preciso

it is necessary

es urgente

it is urgent

es raro

it is strange

es justo

it is fair

es dudoso

it is doubtful

quizás / quizá

perhaps

tal vez

maybe

a lo mejor

maybe, probably

posiblemente

possibly

Sample practice questions

30 more questions like these, from level 1 to 5, are in the practice set.