Infinitive or que clause in Spanish: quiero ir, quiero que vayas, me alegro de que

Why English speakers get this wrong

English says "I want you to go", "I'm sure that he knows", "I realised that it was late" and "I'm glad that you came" with no preposition, so learners write *Quiero tú ir, *Estoy seguro que, *Me di cuenta que, *Me alegro que. Spanish needs Quiero que vayas, Estoy seguro de que, Me di cuenta de que, Me alegro de que. Then many overcorrect: *Pienso de que, *Es posible de que. The Spanish names are queísmo (a missing preposition) and dequeísmo (an extra one).

Infinitive or que clause

When the person who wants, hopes or feels is also the person who acts, Spanish uses the infinitive: Espero aprobar, not *Espero que yo apruebe. For an earlier action by the same subject use the compound infinitive, where English often uses a past tense: Siento no haber llamado antes ("I'm sorry I didn't call earlier", never *Siento que no llamé), Lamentamos haberle causado molestias, Me alegro de haberte conocido, Espero haber respondido a su pregunta.

When the subject changes, use que and a verb: Lamento que no haya podido asistir, Me sorprende que el informe no mencione los costes. A dative pronoun marks who feels: in Me alegra verte the person who is glad is the person who sees; in Me alegra que vengas someone else comes. The same split works in Nos preocupa no llegar a tiempo and Nos preocupa que el tren no llegue a tiempo. After will, emotion and value judgement the verb after que is in the subjunctive: Me sorprende que no haya respondido.

Verbs of influence (permitir, prohibir, mandar, aconsejar, pedir) take either construction with a different subject: Te prohíbo salir and Te prohíbo que salgas are both correct. Likewise Es necesario leer el contrato (as a general rule) and Es necesario que la empresa publique las cuentas (with a named subject) are both fine.

Perception verbs with an infinitive

After ver, oír, escuchar, sentir and notar, Spanish puts the perceived person as an object before the verb and keeps the infinitive: La vi salir ("I saw her leave"), Los oímos discutir, Te noté dudar. Do not add a or a subject pronoun: not *La vi a salir, *Vi ella salir, *Vi la salir. With a noun both orders work: Vi salir a la ministra and Vi a la ministra salir. Not *La vi salió either. Direct perception takes the infinitive (Te oí llegar, "I heard you arrive"); news takes que (Oí que habías llegado, "I heard that you had arrived").

Questions with an infinitive

Indirect questions about what to do keep the infinitive and an accented question word: No sé qué hacer, No tengo claro cómo empezar, No sabía si aceptar o no (si for a yes/no doubt). The C1 point is that the preposition goes before the question word, as it does in a relative clause: No sé a quién dirigirme, No sabía con quién hablar, No sé en quién confiar, No tenían de qué quejarse. English "who to ask" can drop the preposition; Spanish never says *No sé quién preguntar. Mind the accent: No tengo qué decir means "I have nothing to say", while No tengo que decir means "I don't have to say".

A clause as the subject

A noun clause can be the subject of an emotion or value predicate: Que no llamara me dolió, El que no llamara me dolió, El hecho de que la ley se aprobara sin debate preocupa a los juristas. All three openings are correct, and the mood after a clause placed first varies (el hecho de que also takes the indicative), so do not treat it as a trap. What is not optional is agreement: a clause is singular, so the main verb is third person singular even when the clause contains a plural noun. Me molesta que los vecinos hagan ruido, never *Me molestan que, because the subject is the whole clause. Plural verbs belong to plural nouns: Me molestan los ruidos. The phrase is el hecho de que, not *el hecho que.

When the emotion or value predicate comes first, the subjunctive is required: Me sorprende que no haya respondido, Es lógico que la oposición proteste. The indicative there is an error.

Dequeísmo and queísmo: keep the preposition

The test: replace the clause with eso or algo. If you need the preposition there, you need it before que. Me alegro de eso, so Me alegro de que vengas. Pienso eso, so Pienso que tienes razón. The same holds before an infinitive: Me alegro de verte, Insistió en pagar.

With de que or en que: alegrarse de, acordarse de, darse cuenta de, estar seguro de, insistir en, confiar en, and the nouns el hecho de, la noticia de, la idea de, la posibilidad de, la esperanza de. With no preposition: pensar, creer, parecer, decir, opinar, considerar, saber, and es posible / probable / evidente / necesario que, me alegra que, me preocupa que. Note the pair Me alegro de que (a reflexive verb, with de) and Me alegra que (the dative construction, without it). One more contrast: acordar que means "to agree" (Acordaron que la reunión sería el lunes), while acordarse de que means "to remember" (Me acordé de que la reunión era el lunes).