diagnosticar Present Subjunctive Conjugation
diagnosticar — to diagnose
Diagnosticar requires a spelling change from 'c' to 'qu' in all forms: diagnostique, diagnostiques, diagnostique, etc.
diagnosticar Present Subjunctive Forms
When to Use the Present Subjunctive
Use the present subjunctive when expressing doubt, hope, or necessity about a medical finding, such as after phrases like 'Espero que...' or 'Dudo que...'.
Notes on diagnosticar in the Present Subjunctive
This verb has a 'c' to 'qu' spelling change to keep the hard 'k' sound before the letter 'e'. It is otherwise regular in its endings.
Example Sentences
Es importante que el médico diagnostique el problema pronto.
It is important that the doctor diagnoses the problem soon.
él/ella/usted
No creo que me diagnostiquen nada grave.
I don't think they will diagnose me with anything serious.
ellos/ellas/ustedes
Busco un doctor que diagnostique alergias raras.
I am looking for a doctor who diagnoses rare allergies.
él/ella/usted
Common Mistakes
Mistake: diagnostice
Correct: diagnostique
Why: The letter 'c' followed by 'e' sounds like an 's' or 'th'. You must use 'qu' to maintain the hard 'k' sound of the infinitive.
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Related Tenses
Present
yo: diagnostico
The present tense is completely regular: diagnostico, diagnosticas, diagnostica, diagnosticamos, diagnosticáis, diagnostican.
Preterite
yo: diagnostiqué
Diagnosticar is regular except for the 'yo' form, which changes to diagnostiqué.
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.).
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.