Diagnosticar Examples, Sentences and Quiz in Spanish
Introduction
diagnosticar means "to diagnose" in English, and it is a verb you will use constantly once you start speaking Spanish for real. This page shows diagnosticar 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 diagnosticar, 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 diagnosticar
Everyday use
Diagnosticar means to diagnose. The sentences below show it in everyday use, in different tenses and persons.
- Yo diagnostico la enfermedad — "I diagnose the illness"
- Él diagnostica a tiempo — "He diagnoses in time"
- Yo diagnostiqué el problema — "I diagnosed the problem"
- Yo diagnosticaba la enfermedad — "I used to diagnose the illness"
- Yo diagnosticaré a tiempo — "I will diagnose in time"
- Yo he diagnosticado el problema — "I have diagnosed the problem"
In the past and the future
The same verb in the past and the future: the form changes, but the meaning stays the same.
- Él diagnosticó el problema — "He diagnosed the problem"
- Él diagnosticaba la enfermedad — "He used to diagnose the illness"
- Tú diagnosticarás a tiempo — "You will diagnose in time"
- Yo diagnosticaría el problema — "I would diagnose the problem"
- Yo había diagnosticado la enfermedad — "I had diagnosed the illness"
- Nosotros diagnosticamos a tiempo — "We diagnose in time"
Diagnosticar in conversation
The two dialogues below show diagnosticar in natural conversation. Read both parts aloud, then try to continue each dialogue with a sentence of your own.
Dialogue 1
- ¿Tú diagnosticas la enfermedad? — "Do you diagnose the illness?"
- Sí, yo diagnostico la enfermedad cada día. — "Yes, I diagnose the illness every day."
- ¿Y ayer? ¿Tú diagnosticaste a tiempo? — "And yesterday? Did you diagnose in time?"
- Sí, yo diagnostiqué a tiempo. — "Yes, I diagnosed in time."
- Mañana, yo diagnosticaré el problema también. — "Tomorrow, I will diagnose the problem too."
Dialogue 2
- ¿Vosotros diagnosticáis la enfermedad? — "Do you diagnose the illness?"
- Sí, nosotros diagnosticamos la enfermedad los fines de semana. — "Yes, We diagnose the illness at the weekends."
- ¿Y ellos? ¿Ellos diagnostican a tiempo? — "And them? Do they diagnose in time?"
- Sí, ellos diagnostican a tiempo también. — "Yes, They diagnose in time too."
- Mañana nosotros diagnosticaremos a tiempo otra vez. — "Tomorrow we will diagnose in time again."
Useful phrases with diagnosticar
Four patterns you can use with diagnosticar in any conversation. The infinitive stays the same; only the first verb changes.
- Voy a diagnosticar la enfermedad. — "I am going to diagnose the illness."
- Quiero diagnosticar a tiempo. — "I want to diagnose in time."
- Me gusta diagnosticar el problema. — "I like to diagnose the problem."
- Acabo de diagnosticar la enfermedad. — "I have just diagnosed the illness."
Common mistakes with diagnosticar in everyday use
Mistake 1
- Wrong: Ellos diagnostica la enfermedad.
- Right: Ellos diagnostican la enfermedad.
- Why: Ellos needs the ellos form diagnostican. The singular diagnostica belongs with él, ella or a singular noun.
Mistake 2
- Wrong: Todos los días, yo diagnostiqué.
- Right: Todos los días, yo diagnostico.
- Why: Todos los días 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 3
- Wrong: Yo soy diagnosticado a tiempo.
- Right: Yo he diagnosticado a tiempo.
- Why: Spanish perfect tenses use haber, not ser: he diagnosticado, has diagnosticado, ha diagnosticado.
Mistake 4
- Wrong: Ayer, yo diagnostico.
- Right: Ayer, yo diagnostiqué.
- Why: Ayer means yesterday, so the action is finished and needs the preterite (diagnostiqué). The present (diagnostico) is for habits and for now.
Mistake 5
- Wrong: Espero que él diagnostica la enfermedad.
- Right: Espero que él diagnostique la enfermedad.
- Why: After espero que, Spanish needs the present subjunctive: diagnostique. The indicative form would be wrong here.
Quiz: diagnosticar in use
Ten questions on diagnosticar across the tenses. The answers are explained, so read them even when you get a question right.
1. What is the I form of diagnosticar in the present tense?
- (a) diagnostico
- (b) diagnosticarán
- (c) diagnosticamos
- (d) diagnosticasteis
Answer: (a) diagnostico. The I form in the present is diagnostico.
2. What is the he / she form of diagnosticar in the present tense?
- (a) ha diagnosticado
- (b) diagnosticaras
- (c) habíamos diagnosticado
- (d) diagnostica
Answer: (d) diagnostica. The he / she form in the present is diagnostica.
3. What is the he / she form of diagnosticar in the preterite tense?
- (a) diagnosticabas
- (b) diagnosticó
- (c) diagnosticara
- (d) diagnosticaran
Answer: (b) diagnosticó. The he / she form in the preterite is diagnosticó.
4. What is the I form of diagnosticar in the imperfect tense?
- (a) habríamos diagnosticado
- (b) diagnosticaba
- (c) diagnostiquen
- (d) diagnostiques
Answer: (b) diagnosticaba. The I form in the imperfect is diagnosticaba.
5. What is the I form of diagnosticar in the future tense?
- (a) diagnosticaremos
- (b) diagnosticaré
- (c) diagnosticáis
- (d) diagnosticarían
Answer: (b) diagnosticaré. The I form in the future is diagnosticaré.
6. What is the I form of diagnosticar in the present perfect tense?
- (a) diagnosticaré
- (b) hemos diagnosticado
- (c) habrás diagnosticado
- (d) he diagnosticado
Answer: (d) he diagnosticado. The I form in the present perfect is he diagnosticado.
7. Complete the sentence: Espero que él ___ la enfermedad.
- (a) diagnostiquéis
- (b) diagnostiquen
- (c) diagnostique
- (d) diagnostiques
Answer: (c) diagnostique. The he / she form in the present subjunctive is diagnostique.
8. What is the we form of diagnosticar in the present tense?
- (a) diagnosticamos
- (b) diagnosticaréis
- (c) habríamos diagnosticado
- (d) habrían diagnosticado
Answer: (a) diagnosticamos. The we form in the present is diagnosticamos.
9. What is the I form of diagnosticar in the preterite tense?
- (a) diagnosticaríais
- (b) diagnostiqué
- (c) diagnosticaréis
- (d) diagnosticabas
Answer: (b) diagnostiqué. The I form in the preterite is diagnostiqué.
10. What is the they form of diagnosticar in the present tense?
- (a) diagnostican
- (b) diagnosticaría
- (c) habías diagnosticado
- (d) ha diagnosticado
Answer: (a) diagnostican. The they form in the present is diagnostican.
Frequently asked questions about diagnosticar
Is diagnosticar regular?
Diagnosticar is a spelling-changing -ar (c → qu before e) verb: diagnostico, diagnosticas, diagnostica. See the full conjugation of diagnosticar for every tense.
What is the past participle of diagnosticar?
The past participle is diagnosticado, used with haber in the perfect tenses: he diagnosticado. The gerund is diagnosticando, used with estar: estoy diagnosticando.
How do I say “I diagnose” in the past?
For one finished action, use the preterite: Yo diagnostiqué a tiempo. For a habit in the past, use the imperfect: Yo diagnosticaba el problema.
How can I practise diagnosticar?
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.