Decaer Examples, Sentences and Quiz
Decaer means “to decline, to weaken”, and it is one of the verbs you will use every day in Spanish. Decaer means to decline or to weaken, and it is used for health declining, interest fading and an empire falling. It follows the pattern of caer, with the present decaigo and the preterite decaí, and it is the verb for a slow, steady fall. This page shows decaer in real sentences, in short dialogues, and in the mistakes learners make most often, and it finishes with a ten-question quiz so you can test yourself. Every sentence below comes with its English translation, and every form is the correct present-tense form unless the sentence is clearly marked as past or future. For a first taste: “Yo decaigo con la edad y la enfermedad.” — I decline with age and illness.
Decaer in real example sentences
The twelve sentences below are grouped by how decaer is used. Read each one out loud, then read the translation. If a sentence feels useful, copy it into your own notebook with one small change — a different time, a different person, a different place — and you have a new sentence of your own.
In the present: everyday use
These sentences use decaer in the present tense, which is how you will meet it most often: routines, facts, and things happening now.
“Decaigo con la edad y la enfermedad.” — I decline with age and illness.
“¿Tú decaes poco a poco tras la crisis?” — Do you decline little by little after the crisis?
“Decae el interés por el proyecto.” — He/she declines interest in the project.
“Decaemos la economía del país.” — We decline the country's economy.
Talking about the past
The present is not the only tense you need. These sentences show decaer in the past, so you can talk about what already happened.
“Ayer, yo decaí con la edad y la enfermedad.” — Yesterday, I declined with age and illness. (preterite)
“Él decaía poco a poco tras la crisis todos los días.” — He used to decline little by little after the crisis every day. (imperfect)
Plans and things already done
These sentences look forward, or look back at something already finished. Notice how the verb form changes while the meaning of decaer stays the same.
“Nosotros decaeremos el interés por el proyecto mañana.” — We will decline interest in the project tomorrow. (future)
“¿Tú has decaído la economía del país?” — Have you declined the country's economy? (present perfect)
More everyday uses
Four more present-tense sentences, covering the remaining persons, so you can see the whole table in action.
“Decaéis con la edad y la enfermedad.” — You decline with age and illness.
“Decaen poco a poco tras la crisis.” — They decline little by little after the crisis.
“Decaigo el interés por el proyecto.” — I decline interest in the project.
“Decae la economía del país.” — He/she declines the country's economy.
Decaer in context
Single sentences teach you the forms. Dialogues teach you when to use them. Read the short conversation below, then the paragraph that follows, and notice how decaer appears naturally, without anyone stopping to think about conjugation.
A short dialogue
Lucía: “¿Tú decaes con la edad y la enfermedad?” — Do you decline with age and illness?
Carlos: “Sí, yo decaigo con la edad y la enfermedad.” — Yes, I decline with age and illness.
Lucía: “Nosotros decaemos poco a poco tras la crisis.” — We decline little by little after the crisis.
Carlos: “Y ellos decaen el interés por el proyecto.” — And they decline interest in the project.
Lucía: “Vosotros decaéis la economía del país.” — You decline the country's economy.
Carlos: “Sí, y él decae poco a poco tras la crisis.” — Yes, and he declines little by little after the crisis.
A short paragraph
Lucía decae con la edad y la enfermedad, y Carlos decae poco a poco tras la crisis. Nosotros decaemos el interés por el proyecto, y ellos decaen la economía del país. Yo decaigo el interés por el proyecto, y mi padre decae la economía del país. Decaer is part of everyday life, because to decline, to weaken is something Spanish speakers do again and again, in every tense and every situation.
Common mistakes with decaer
These are the errors learners actually make with decaer. Each one shows the wrong version, the right version, and why the correction matters.
Wrong: “Yo decae con la edad y la enfermedad.” Right: “Yo decaigo con la edad y la enfermedad.” Why: The person matters: decae is the él/ella/Ud. form, while the yo form is decaigo. Using the third-person form with yo is one of the most common beginner errors.
Wrong: “Yo he decaido el interés por el proyecto.” Right: “Yo he decaído el interés por el proyecto.” Why: The past participle of decaer is irregular: decaído, not decaido. Every perfect tense uses he decaído, había decaído and so on.
Wrong: “Treating decaer and mejorar as identical in every context.” Right: “Decaer means to decline, to weaken, while mejorar means to improve.” Why: They overlap, but each has uses the other does not: decaer fits sentences such as Decaigo con la edad y la enfermedad, while mejorar belongs in a different sentence. Check the meaning you want before choosing.
Wrong: “Yo soy decaído poco a poco tras la crisis.” Right: “Yo he decaído poco a poco tras la crisis.” Why: Spanish perfect tenses use haber, not ser: he decaído, has decaído, ha decaído. Ser plus the participle makes a passive, not a perfect tense.
Wrong: “De niño, yo decaí el interés por el proyecto todos los días.” Right: “De niño, yo decaía el interés por el proyecto todos los días.” Why: For a repeated habit in the past, use the imperfect (decaía), not the preterite. The preterite (decaí) is for one finished action.
Quiz: decaer in use
Ten questions on decaer in real sentences. Choose the correct answer for each one, then check the answer key. Every answer is explained.
1. Complete the sentence: “Vosotros ______ con la edad y la enfermedad.” (With age and illness.)
- (a) decaéis
- (b) decaigo
- (c) decaes
Answer: decaéis — The vosotros/as form of decaer in the present is decaéis.
2. Complete the sentence: “Ellos ______ poco a poco tras la crisis.” (Little by little after the crisis.)
- (a) decaigo
- (b) decaes
- (c) decaen
Answer: decaen — The ellos/ellas/Uds. form of decaer in the present is decaen.
3. Complete the sentence: “Yo ______ con la edad y la enfermedad.” (With age and illness.)
- (a) decayó
- (b) decaí
- (c) decaíste
Answer: decaí — The yo form of decaer in the preterite is decaí.
4. Complete the sentence: “Él ______ poco a poco tras la crisis.” (Little by little after the crisis.)
- (a) decaía
- (b) decaías
- (c) decaíamos
Answer: decaía — The él/ella/Ud. form of decaer in the imperfect is decaía.
5. Complete the sentence: “Nosotros ______ el interés por el proyecto.” (Interest in the project.)
- (a) decaeré
- (b) decaerás
- (c) decaeremos
Answer: decaeremos — The nosotros/as form of decaer in the future is decaeremos.
6. What does decaer mean in English?
- (a) to relapse, to fall again
- (b) to decline, to weaken
- (c) to improve
Answer: to decline, to weaken — Decaer means “to decline, to weaken”. The other options are the meanings of different verbs.
7. Which sentence is correct?
- (a) Yo decaigo con la edad y la enfermedad.
- (b) Ellos decae con la edad y la enfermedad.
- (c) Yo decaigo poco a poco tras la crisis ayer.
Answer: Yo decaigo con la edad y la enfermedad. — “Yo decaigo con la edad y la enfermedad.” is correct. The other two sentences contain the mistakes explained in the section above.
8. How do you say “I decline with age and illness.” in Spanish?
- (a) Yo decaen con la edad y la enfermedad.
- (b) Yo decaí con la edad y la enfermedad.
- (c) Yo decaigo con la edad y la enfermedad.
Answer: Yo decaigo con la edad y la enfermedad. — “Yo decaigo con la edad y la enfermedad.” is the correct translation. The second option uses the wrong person's form, and the third uses the preterite.
9. What is the nosotros form of decaer in the present tense?
- (a) decaes
- (b) decaemos
- (c) decaigo
Answer: decaemos — The nosotros form is decaemos.
10. Which of these sentences is in the present tense?
- (a) Ayer, yo decaí con la edad y la enfermedad.
- (b) Nosotros decaeremos con la edad y la enfermedad mañana.
- (c) Yo decaigo con la edad y la enfermedad.
Answer: Yo decaigo con la edad y la enfermedad. — “Yo decaigo con la edad y la enfermedad.” is in the present tense. The other two are in the preterite and the future.
Frequently asked questions
How do you say 'I decline' in Spanish?
Say 'Yo decaigo con la edad y la enfermedad'. The complement follows directly, as in the examples above. For a routine, add a time expression: 'Yo decaigo con la edad y la enfermedad todos los días'.
How do you say 'I decline' in the past?
For one finished action, say 'Ayer, yo decaí poco a poco tras la crisis'. For a repeated habit, say 'Yo decaía poco a poco tras la crisis todos los días'. For something already done, say 'Yo he decaído poco a poco tras la crisis'.
What is the difference between decaer and mejorar?
Decaer means to decline, to weaken, while mejorar means to improve. They are easy to confuse because they appear in similar situations, but they are not interchangeable: use decaer when you mean to decline, to weaken, as in Decaigo con la edad y la enfermedad.
Related pages
- Full conjugation of decaer — every tense of decaer in one place.
- Decaer in the preterite tense — the full table and usage rules for one tense.
- Spanish verbs — the hub for every Spanish verb on VerbFlow.
- Verb quiz — test yourself on decaer and other verbs.
- Conjugation practice — drill the forms of decaer until they are automatic.