diagnosticar Preterite Conjugation
diagnosticar — to diagnose
Diagnosticar is regular except for the 'yo' form, which changes to diagnostiqué.
diagnosticar Preterite Forms
When to Use the Preterite
Use the preterite to talk about the specific moment a doctor or expert identified a condition or problem in the past.
Notes on diagnosticar in the Preterite
There is a spelling change in the 'yo' form (diagnostiqué) to preserve the hard 'k' sound. All other forms are regular -ar preterite endings.
Example Sentences
Ayer el mecánico diagnosticó el fallo del motor.
Yesterday the mechanic diagnosed the engine failure.
él/ella/usted
Yo diagnostiqué el problema antes que nadie.
I diagnosed the problem before anyone else.
yo
Los médicos diagnosticaron su gripe el lunes.
The doctors diagnosed her flu on Monday.
ellos/ellas/ustedes
Common Mistakes
Mistake: diagnosticé
Correct: diagnostiqué
Why: Using 'c' instead of 'qu' would change the pronunciation to 'diagnostis-é'.
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Related Tenses
Present
yo: diagnostico
The present tense is completely regular: diagnostico, diagnosticas, diagnostica, diagnosticamos, diagnosticáis, diagnostican.
Imperfect
yo: diagnosticaba
The imperfect is regular: diagnosticaba, diagnosticabas, diagnosticaba, diagnosticábamos, diagnosticabais, diagnosticaban.
Future
yo: diagnosticaré
The future tense is regular: add endings to the infinitive (diagnosticaré, diagnosticarás, etc.).
Conditional
yo: diagnosticaría
The conditional is regular: add -ía endings to the infinitive (diagnosticaría, diagnosticarías, etc.).
Present Subjunctive
yo: diagnostique
Diagnosticar requires a spelling change from 'c' to 'qu' in all forms: diagnostique, diagnostiques, diagnostique, etc.
Imperfect Subjunctive
yo: diagnosticara
The imperfect subjunctive follows the -ra pattern: diagnosticara, diagnosticaras, diagnosticara, etc.
Affirmative Imperative
yo: diagnostica
The imperative uses 'diagnostica' (tú) and 'diagnostique' (usted/ustedes).
Negative Imperative
yo: no diagnostiques
The negative imperative always uses the present subjunctive forms: no diagnostiques, no diagnostique, etc.