Ella Verbsdiagnosticar to diagnose, to identify Irregular Verb
At a glance: Diagnosticar (to diagnose, to identify) is a irregular verb in Spanish. In the present tense: diagnostico, diagnosticas, diagnostica, diagnosticamos, diagnosticáis, diagnostican. The present tense is regular. In the preterite: yo changes c to qu (diagnostiqué); the other forms are regular. It is also irregular in the present subjunctive (diagnostique).

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The Indicative Present of diagnosticar is used to talk about situations, events or thoughts that are happening now or in the near future. It is also used to talk about facts and truths. For example, “diagnostico”, meaning “I diagnose”.
In Spanish, the Indicative Present is known as "El Presente".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnostico | I diagnose |
| Tú | diagnosticas | you diagnose |
| Ella / Él / Usted | diagnostica | s/he diagnoses |
| Nosotras / Nosotros | diagnosticamos | we diagnose |
| Vosotras / Vosotros | diagnosticáis | you (plural) diagnose |
| Ellas / Ellos / Ustedes | diagnostican | they diagnose |
How it’s built: Regular: stem diagnostic- plus the -ar endings.
The Indicative Preterite of diagnosticar is used to talk about actions completed in the past, at a specific point in time. For example, “diagnostiqué”, meaning “I diagnosed”.
In Spanish, the Indicative Preterite is known as "El Pretérito Indefinido".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnostiqué | I diagnosed |
| Tú | diagnosticaste | you diagnosed |
| Ella / Él / Usted | diagnosticó | s/he diagnosed |
| Nosotras / Nosotros | diagnosticamos | we diagnosed |
| Vosotras / Vosotros | diagnosticasteis | you (plural) diagnosed |
| Ellas / Ellos / Ustedes | diagnosticaron | they diagnosed |
How it’s built: Yo changes c to qu (diagnostiqué); the other forms are regular.
Letters in red show where a form differs from the regular pattern.
The Indicative Imperfect of diagnosticar is used to describe regular and repeated actions that happened in the past and descriptions of things you used to do. For example, “diagnosticaba”, meaning “I used to diagnose”.
In Spanish, the Indicative Imperfect is known as "El Pretérito Imperfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnosticaba | I used to diagnose |
| Tú | diagnosticabas | you used to diagnose |
| Ella / Él / Usted | diagnosticaba | s/he used to diagnose |
| Nosotras / Nosotros | diagnosticábamos | we used to diagnose |
| Vosotras / Vosotros | diagnosticabais | you (plural) used to diagnose |
| Ellas / Ellos / Ustedes | diagnosticaban | they used to diagnose |
How it’s built: Regular: stem diagnostic- plus the -ar endings.
The Indicative Present Continuous of diagnosticar is used to talk about something that is happening continuously or right now. For example, “estoy diagnosticando”, meaning “I am diagnosing”.
In Spanish, the Indicative Present Continuous is known as "El Presente Progresivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | estoy diagnosticando | I am diagnosing |
| Tú | estás diagnosticando | you are diagnosing |
| Ella / Él / Usted | está diagnosticando | s/he is diagnosing |
| Nosotras / Nosotros | estamos diagnosticando | we are diagnosing |
| Vosotras / Vosotros | estáis diagnosticando | you (plural) are diagnosing |
| Ellas / Ellos / Ustedes | están diagnosticando | they are diagnosing |
How it’s built: Estar in the present (estoy, estás, está, estamos, estáis, están) plus the gerund diagnosticando.
The Indicative Informal Future of diagnosticar is used to talk about something that will happen in the future, especially in the near future. For example, “voy a diagnosticar”, meaning “I am going to diagnose”.
In Spanish, the Indicative Informal Future is known as "El Futuro Próximo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | voy a diagnosticar | I am going to diagnose |
| Tú | vas a diagnosticar | you are going to diagnose |
| Ella / Él / Usted | va a diagnosticar | s/he is going to diagnose |
| Nosotras / Nosotros | vamos a diagnosticar | we are going to diagnose |
| Vosotras / Vosotros | vais a diagnosticar | you (plural) are going to diagnose |
| Ellas / Ellos / Ustedes | van a diagnosticar | they are going to diagnose |
How it’s built: Ir in the present (voy, vas, va, vamos, vais, van), then a, then the infinitive diagnosticar.
The Indicative Future of diagnosticar is used to talk about something that will happen in the future. For example, “diagnosticaré”, meaning “I will diagnose”.
In Spanish, the Indicative Future is known as "El Futuro Simple".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnosticaré | I will diagnose |
| Tú | diagnosticarás | you will diagnose |
| Ella / Él / Usted | diagnosticará | s/he will diagnose |
| Nosotras / Nosotros | diagnosticaremos | we will diagnose |
| Vosotras / Vosotros | diagnosticaréis | you (plural) will diagnose |
| Ellas / Ellos / Ustedes | diagnosticarán | they will diagnose |
How it’s built: Regular: the infinitive diagnosticar plus the future endings.
The Indicative Conditional of diagnosticar is used to talk about something that may happen in the future, hypothesis and probabilities. For example, “diagnosticaría”, meaning “I would diagnose”.
In Spanish, the Indicative Conditional is known as "El Condicional Simple".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnosticaría | I would diagnose |
| Tú | diagnosticarías | you would diagnose |
| Ella / Él / Usted | diagnosticaría | s/he would diagnose |
| Nosotras / Nosotros | diagnosticaríamos | we would diagnose |
| Vosotras / Vosotros | diagnosticaríais | you (plural) would diagnose |
| Ellas / Ellos / Ustedes | diagnosticarían | they would diagnose |
How it’s built: Regular: the infinitive diagnosticar plus the conditional endings.
The Indicative Present Perfect of diagnosticar is used to describe actions that started recently (in the past) and are still happening now or things that have been done recently. For example, “he diagnosticado”, meaning “I have diagnosed”.
In Spanish, the Indicative Present Perfect is known as "El Pretérito Perfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | he diagnosticado | I have diagnosed |
| Tú | has diagnosticado | you have diagnosed |
| Ella / Él / Usted | ha diagnosticado | s/he has diagnosed |
| Nosotras / Nosotros | hemos diagnosticado | we have diagnosed |
| Vosotras / Vosotros | habéis diagnosticado | you (plural) have diagnosed |
| Ellas / Ellos / Ustedes | han diagnosticado | they have diagnosed |
How it’s built: Haber in the present (he, has, ha, hemos, habéis, han) plus the past participle diagnosticado.
The Indicative Past Perfect of diagnosticar is used to talk about actions that happened before another action in the past. For example, “había diagnosticado”, meaning “I had diagnosed”.
In Spanish, the Indicative Past Perfect is known as "El Pretérito Pluscuamperfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | había diagnosticado | I had diagnosed |
| Tú | habías diagnosticado | you had diagnosed |
| Ella / Él / Usted | había diagnosticado | s/he had diagnosed |
| Nosotras / Nosotros | habíamos diagnosticado | we had diagnosed |
| Vosotras / Vosotros | habíais diagnosticado | you (plural) had diagnosed |
| Ellas / Ellos / Ustedes | habían diagnosticado | they had diagnosed |
How it’s built: Haber in the imperfect (había, habías, había, habíamos, habíais, habían) plus the past participle diagnosticado.
The Indicative Future Perfect of diagnosticar is used to talk about something that will have happened in the future after something else has already happened. For example, “habré diagnosticado”, meaning “I will have diagnosed”.
In Spanish, the Indicative Future Perfect is known as "El Futuro Perfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | habré diagnosticado | I will have diagnosed |
| Tú | habrás diagnosticado | you will have diagnosed |
| Ella / Él / Usted | habrá diagnosticado | s/he will have diagnosed |
| Nosotras / Nosotros | habremos diagnosticado | we will have diagnosed |
| Vosotras / Vosotros | habréis diagnosticado | you (plural) will have diagnosed |
| Ellas / Ellos / Ustedes | habrán diagnosticado | they will have diagnosed |
How it’s built: Haber in the future (habré, habrás, habrá, habremos, habréis, habrán) plus the past participle diagnosticado.
The Indicative Conditional Perfect of diagnosticar is used to talk about something that would have happened in the past but didn’t due to another action. For example, “habría diagnosticado”, meaning “I would have diagnosed”.
In Spanish, the Indicative Conditional Perfect is known as "El Condicional Perfecto".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | habría diagnosticado | I would have diagnosed |
| Tú | habrías diagnosticado | you would have diagnosed |
| Ella / Él / Usted | habría diagnosticado | s/he would have diagnosed |
| Nosotras / Nosotros | habríamos diagnosticado | we would have diagnosed |
| Vosotras / Vosotros | habríais diagnosticado | you (plural) would have diagnosed |
| Ellas / Ellos / Ustedes | habrían diagnosticado | they would have diagnosed |
How it’s built: Haber in the conditional (habría, habrías, habría, habríamos, habríais, habrían) plus the past participle diagnosticado.
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The Subjunctive Present is used to talk about situations of uncertainty, or emotions such as wishes, desires and hopes. It differs from the indicative mood due to the uncertainty of the events which are being spoken about. For example, “diagnostique”, meaning “I diagnose”.
In Spanish, the Subjunctive Present is known as "El Presente de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnostique | I diagnose |
| Tú | diagnostiques | you diagnose |
| Ella / Él / Usted | diagnostique | s/he diagnoses |
| Nosotras / Nosotros | diagnostiquemos | we diagnose |
| Vosotras / Vosotros | diagnostiquéis | you (plural) diagnose |
| Ellas / Ellos / Ustedes | diagnostiquen | they diagnose |
How it’s built: Every form changes c to qu (diagnostique, diagnostiques, diagnostique, diagnostiquemos, diagnostiquéis, diagnostiquen).
Letters in red show where a form differs from the regular pattern.
The Subjunctive Imperfect is used to speak about unlikely or uncertain events in the past or to cast an opinion (emotional) about something that happened in the past. For example, “diagnosticara”, meaning “I diagnosed”.
In Spanish, the Subjunctive Imperfect is known as "El Imperfecto Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnosticara | I diagnosed |
| Tú | diagnosticaras | you diagnosed |
| Ella / Él / Usted | diagnosticara | s/he diagnosed |
| Nosotras / Nosotros | diagnosticáramos | we diagnosed |
| Vosotras / Vosotros | diagnosticarais | you (plural) diagnosed |
| Ellas / Ellos / Ustedes | diagnosticaran | they diagnosed |
How it’s built: Regular: the ellas/ellos preterite, diagnosticaron, without -ron, plus the -ra endings; nosotros adds an accent (diagnosticáramos).
The Subjunctive Future is used to speak about hypothetical situations, and actions/events that may happen in the future. For example, “diagnosticare”, meaning “I will diagnose”.
In Spanish, the Subjunctive Future is known as "El Futuro de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | diagnosticare | I will diagnose |
| Tú | diagnosticares | you will diagnose |
| Ella / Él / Usted | diagnosticare | s/he will diagnose |
| Nosotras / Nosotros | diagnosticáremos | we will diagnose |
| Vosotras / Vosotros | diagnosticareis | you (plural) will diagnose |
| Ellas / Ellos / Ustedes | diagnosticaren | they will diagnose |
How it’s built: Regular: the ellas/ellos preterite, diagnosticaron, without -ron, plus the -re endings; nosotros adds an accent (diagnosticáremos).
The Subjunctive Present Perfect is used to describe past actions or events that are still connected to the present day and to speak about an action that will have happened by a certain time in the future. For example, “haya diagnosticado”, meaning “I have diagnosed”.
In Spanish, the Subjunctive Present Perfect is known as "El Pretérito Perfecto de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | haya diagnosticado | I have diagnosed |
| Tú | hayas diagnosticado | you have diagnosed |
| Ella / Él / Usted | haya diagnosticado | s/he has diagnosed |
| Nosotras / Nosotros | hayamos diagnosticado | we have diagnosed |
| Vosotras / Vosotros | hayáis diagnosticado | you (plural) have diagnosed |
| Ellas / Ellos / Ustedes | hayan diagnosticado | they have diagnosed |
How it’s built: Haber in the subjunctive present (haya, hayas, haya, hayamos, hayáis, hayan) plus the past participle diagnosticado.
The Subjunctive Past Perfect is used to speak about hypothetical situations, and actions/events that occurred before other actions/events in the past. For example, “hubiera diagnosticado”, meaning “I had diagnosed”.
In Spanish, the Subjunctive Past Perfect is known as "El Pretérito Pluscuamperfecto de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | hubiera diagnosticado | I had diagnosed |
| Tú | hubieras diagnosticado | you had diagnosed |
| Ella / Él / Usted | hubiera diagnosticado | s/he had diagnosed |
| Nosotras / Nosotros | hubiéramos diagnosticado | we had diagnosed |
| Vosotras / Vosotros | hubierais diagnosticado | you (plural) had diagnosed |
| Ellas / Ellos / Ustedes | hubieran diagnosticado | they had diagnosed |
How it’s built: Haber in the subjunctive imperfect (hubiera, hubieras, hubiera, hubiéramos, hubierais, hubieran) plus the past participle diagnosticado.
The Subjunctive Future Perfect is used to speak about something that will have happened if a hypothetical situations occurs in the future. For example, “hubiere diagnosticado”, meaning “I will have diagnosed”.
In Spanish, the Subjunctive Future Perfect is known as "El Futuro Perfecto de Subjuntivo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | hubiere diagnosticado | I will have diagnosed |
| Tú | hubieres diagnosticado | you will have diagnosed |
| Ella / Él / Usted | hubiere diagnosticado | s/he will have diagnosed |
| Nosotras / Nosotros | hubiéremos diagnosticado | we will have diagnosed |
| Vosotras / Vosotros | hubiereis diagnosticado | you (plural) will have diagnosed |
| Ellas / Ellos / Ustedes | hubieren diagnosticado | they will have diagnosed |
How it’s built: Haber in the subjunctive future (hubiere, hubieres, hubiere, hubiéremos, hubiereis, hubieren) plus the past participle diagnosticado.
The Imperative Affirmative is used to give orders and commands, to tell someone to do something. For example, “diagnostique”, meaning “(to you formal) diagnose!”.
In Spanish, the Imperative Affirmative is known as "El Imperativo Afirmativo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | - | - |
| Tú | diagnostica | (to you) diagnose! |
| Ella / Él / Usted | diagnostique | (to you formal) diagnose! |
| Nosotras / Nosotros | diagnostiquemos | let's diagnose! |
| Vosotras / Vosotros | diagnosticad | (to you plural) diagnose! |
| Ellas / Ellos / Ustedes | diagnostiquen | (to you plural formal) diagnose! |
How it’s built: Tú takes the ella/él present (diagnostica); usted, nosotros and ustedes take the subjunctive present (diagnostique, diagnostiquemos, diagnostiquen); vosotros swaps the final r of the infinitive for a d (diagnosticad).
Letters in red show where a form differs from the regular pattern.
The Imperative Negative is used to give orders and commands, telling someone not to do something. For example, “no diagnostique”, meaning “(to you formal) don't diagnose!”.
In Spanish, the Imperative Negative is known as "El Imperativo Negativo".
| Pronoun | Spanish | English |
|---|---|---|
| Yo | - | - |
| Tú | no diagnostiques | (to you) don't diagnose! |
| Ella / Él / Usted | no diagnostique | (to you formal) don't diagnose! |
| Nosotras / Nosotros | no diagnostiquemos | let's not diagnose! |
| Vosotras / Vosotros | no diagnostiquéis | (to you plural) don't diagnose! |
| Ellas / Ellos / Ustedes | no diagnostiquen | (to you plural formal) don't diagnose! |
How it’s built: No plus the subjunctive present: no diagnostiques, no diagnostique, no diagnostiquemos, no diagnostiquéis, no diagnostiquen.
Letters in red show where a form differs from the regular pattern.
Diagnosticar is an irregular Spanish verb. The present tense is regular. In the preterite: yo changes c to qu (diagnostiqué); the other forms are regular. It is also irregular in the present subjunctive (diagnostique).
In the present tense (presente), diagnosticar is conjugated as: yo diagnostico, tú diagnosticas, él/ella/usted diagnostica, nosotros diagnosticamos, vosotros diagnosticáis, ellos/ellas/ustedes diagnostican. The present tense is used To talk about situations, events or thoughts that are happening now or in the near future. It is also used to talk about facts and truths.
In the preterite (pretérito indefinido), diagnosticar is conjugated as: yo diagnostiqué, tú diagnosticaste, él/ella/usted diagnosticó, nosotros diagnosticamos, vosotros diagnosticasteis, ellos/ellas/ustedes diagnosticaron. The preterite is used To talk about actions completed in the past, at a specific point in time.
In the imperfect (pretérito imperfecto), diagnosticar is conjugated as: yo diagnosticaba, tú diagnosticabas, él/ella/usted diagnosticaba, nosotros diagnosticábamos, vosotros diagnosticabais, ellos/ellas/ustedes diagnosticaban. The imperfect is used To describe regular and repeated actions that happened in the past and descriptions of things you used to do.
In the future tense (futuro simple), diagnosticar is conjugated as: yo diagnosticaré, tú diagnosticarás, él/ella/usted diagnosticará, nosotros diagnosticaremos, vosotros diagnosticaréis, ellos/ellas/ustedes diagnosticarán. The future tense is used To talk about something that will happen in the future.
In the present subjunctive (subjuntivo presente), diagnosticar is conjugated as: yo diagnostique, tú diagnostiques, él/ella/usted diagnostique, nosotros diagnostiquemos, vosotros diagnostiquéis, ellos/ellas/ustedes diagnostiquen. The present subjunctive is used To talk about situations of uncertainty, or emotions such as wishes, desires and hopes. It differs from the indicative mood due to the uncertainty of the events which are being spoken about.
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