Dudar Examples, Sentences and Quiz in Spanish
Introduction
dudar means "to doubt" in English, and it is a verb you will use constantly once you start speaking Spanish for real. This page shows dudar in everyday sentences, grouped by meaning, then puts it into two short conversations, lists the mistakes learners actually make, and finishes with a ten-question quiz and answers to the most common questions. Every sentence below uses a real form of dudar, so you can copy the patterns and change the person, the tense and the complement to make your own versions. Start with the examples, say them aloud, and then try the quiz without looking back.
Example sentences with dudar
Doubting a fact or a person
Dudar de algo means you are not sure something is true: dudo de su palabra, dudo de la decisión. The verb takes de before the thing you doubt, which is the first thing to learn about it.
- Cada día, yo dudo de su palabra. — "Every day, I doubt his word."
- Hoy, él / ella duda de la decisión. — "Today, he / she doubts the decision."
- Ayer, yo dudé de mis respuestas. — "Yesterday, I doubted my answers."
- Antes, yo dudaba de todo. — "Before, I used to doubt everything."
- Mañana, yo dudaré de su palabra. — "Tomorrow, I will doubt his word."
- Hoy, yo he dudado de la decisión. — "Today, I have doubted the decision."
Dudar que and the subjunctive
When dudar introduces a clause with que, it triggers the subjunctive: dudo que sea verdad. This is one of the clearest subjunctive triggers in Spanish, and it is the reason learners meet dudar early.
- Cada día, yo dudo de mis respuestas. — "Every day, I doubt my answers."
- Hoy, él / ella duda de todo. — "Today, he / she doubts everything."
- Ayer, yo dudé de su palabra. — "Yesterday, I doubted his word."
- Antes, yo dudaba de la decisión. — "Before, I used to doubt the decision."
- Mañana, yo dudaré de mis respuestas. — "Tomorrow, I will doubt my answers."
- Hoy, yo he dudado de todo. — "Today, I have doubted everything."
Dudar in conversation
The two dialogues below show dudar in natural conversation. The first is about doubting a fact or a person, and the second is about dudar que and the subjunctive. Read both parts aloud, then try to continue each dialogue with a sentence of your own.
Dialogue 1
- ¿Tú dudas de su palabra? — "Do you doubt his word?"
- Sí, yo dudo de su palabra cada día. — "Yes, I doubt his word every day."
- ¿Y ayer? ¿Tú dudaste de la decisión? — "And yesterday? Did you doubt the decision?"
- Sí, ayer yo dudé de la decisión. — "Yes, yesterday I doubted the decision."
- Mañana yo dudaré de mis respuestas también. — "Tomorrow I will doubt my answers too."
Dialogue 2
- ¿Vosotros dudáis de mis respuestas? — "Do you doubt my answers?"
- Sí, nosotros dudamos de mis respuestas los fines de semana. — "Yes, we doubt my answers at the weekends."
- ¿Y ellos? ¿Ellos dudan de todo? — "And them? Do they doubt everything?"
- Sí, ellos dudan de todo también. — "Yes, they doubt everything too."
- Mañana nosotros dudaremos de mis respuestas otra vez. — "Tomorrow we will doubt my answers again."
Common mistakes with dudar in everyday use
Mistake 1
- Wrong: Yo dudo su palabra.
- Right: Yo dudo de su palabra.
- Why: Dudar takes de before the thing you doubt. Without de the sentence is wrong: dudo de su palabra, dudo de la decisión, dudo de todo.
Mistake 2
- Wrong: Dudo que es verdad.
- Right: Dudo que sea verdad.
- Why: After dudo que, Spanish requires the subjunctive, not the indicative. Dudo que es verdad is one of the most frequent subjunctive mistakes learners make.
Mistake 3
- Wrong: Dudar es lo mismo que no saber.
- Right: Dudar means to doubt; no saber means not to know.
- Why: You can know all the facts and still dudar, because doubt is about confidence, not information. No saber is about missing information.
Mistake 4
- Wrong: Cada día, yo dudé de su palabra.
- Right: Cada día, yo dudo de su palabra.
- Why: Cada día means every day, so the action is a habit and needs the present tense. The preterite is for one finished action, not for routines.
Mistake 5
- Wrong: Yo dudo de su palabra ayer por la mañana.
- Right: Ayer por la mañana yo dudé de su palabra.
- Why: Ayer por la mañana means yesterday morning, so the action is finished and needs the preterite, not the present.
Quiz: dudar in use
Ten questions on dudar across the tenses. The answers are explained, so read them even when you get a question right.
1. What is the i form of dudar in the present tense?
- (a) duda
- (b) dudamos
- (c) dudo
- (d) dudas
Answer: (c) dudo. The i form in the present is dudo.
2. What is the he / she form of dudar in the present tense?
- (a) dudamos
- (b) duda
- (c) dudo
- (d) dudas
Answer: (b) duda. The he / she form in the present is duda.
3. What is the he / she form of dudar in the preterite tense?
- (a) dudó
- (b) dudé
- (c) dudaste
- (d) dudamos
Answer: (a) dudó. The he / she form in the preterite is dudó.
4. What is the i form of dudar in the imperfect tense?
- (a) dudo
- (b) dudé
- (c) dudaré
- (d) dudaba
Answer: (d) dudaba. The i form in the imperfect is dudaba. The other options are the same person in the present, preterite and future.
5. What is the i form of dudar in the future tense?
- (a) dudará
- (b) dudaremos
- (c) dudaré
- (d) dudarás
Answer: (c) dudaré. The i form in the future is dudaré.
6. Which is the correct present perfect form for i?
- (a) dudé
- (b) dudaba
- (c) dudo
- (d) he dudado
Answer: (d) he dudado. The present perfect is haber + the past participle: he dudado.
7. Complete the sentence: Espero que él ___ de su palabra.
- (a) dudaba
- (b) dude
- (c) duda
- (d) dudó
Answer: (b) dude. After espero que, Spanish needs the present subjunctive: dude. The indicative form would be wrong here.
8. What is the we form of dudar in the present tense?
- (a) dudo
- (b) dudas
- (c) duda
- (d) dudamos
Answer: (d) dudamos. The we form in the present is dudamos.
9. What is the i form of dudar in the preterite tense?
- (a) dudó
- (b) dudamos
- (c) dudé
- (d) dudaste
Answer: (c) dudé. The i form in the preterite is dudé.
10. What is the they form of dudar in the present tense?
- (a) duda
- (b) dudan
- (c) dudo
- (d) dudas
Answer: (b) dudan. The they form in the present is dudan.
Frequently asked questions about dudar
Does dudar take de or en?
Dudar takes de: dudo de su palabra. Do not confuse it with confiar, which takes en: confío en ti. The two verbs are opposites in meaning and opposite in preposition.
Why does dudar trigger the subjunctive?
Because doubt is not a fact. Spanish puts the verb after dudo que in the subjunctive to show that the speaker is not stating something true, only something uncertain.
What is the difference between dudar and sospechar?
Dudar means you are unsure whether something is true. Sospechar means you believe something bad or hidden is probably true. They point in opposite directions.
How can I practise dudar?
Start with the examples above: say each sentence aloud, then change the person and the complement. Then take the quiz, and finish with the Verb Quiz and the Conjugation Practice tools, which test the same forms in a different order. A few minutes a day with one verb is worth more than an hour once a week.