Among these listed verbs, it is only TRABAJAR and DEBER that keep a regular (uniform) pattern.  

In fact, DEBER (must) is one of the words that we are lately being drilled with, so it is quite ‘regular’(usual). As per the above premise, the more you use it, the more you deform it, it might become an irregular verb if the covid persists. I hope not!

Debes ponerte la mascarilla (you must wear the mask), no debes reunirte (you must avoid gathering together)…

As far as TRABAJAR is concerned, unfortunately, we couldn’t say it is so ‘regular’ (usual) in Spain, taking into account the unemployment rate.

All the other verbs show any irregularity, so they could be considered common irregular verbs.

 Present indicative:

-     Vocalic irregularity: O changes into UE:

PODER: puedo, puedes, puede, podemos podéis, pueden

-     Irregularity only on the first singular person: yo

ESTAR: estoy, estás, está, estamos, estáis, están

HACER: hago, haces, hace, hacemos, hacéis, hacen

-     Irregularity on more than one person:

TENER: tengo, tienes, tiene, tenemos, tenéis, tienen

DECIR: digo, dices, dice, decimos, decís, dicen

HABER: he, has, ha, hemos, habéis, han – impersonal: hay

-     Completely irregular:

SER: soy, eres, es, somos, sois, son

IR: voy, vas, va, vamos, vais, van

Present subjunctive:

Present indicative first person singular (YO) is taken as the root to conjugate present subjunctive. So all these verbs keep their irregularity patterns, except for HABER, SER, and IR.

PODER > PUEDO > PUED- (root)

pueda, puedas, pueda, podamos, podáis, puedan.

HACER > HAGO > HAG- (root)

haga, hagas, haga, hagamos, hagáis, hagan.

HABER: haya, hayas, haya, hayamos, hayáis, hayan

SER: sea, seas, sea, seamos, seáis, sean

IR: vaya, vayas, vaya, vayamos, vayáis, vayan

Past simple (indefinido):

        PODER: pude, pudiste, pudo, pudimos, pudisteis, pudieron

        ESTAR: estuve, estuviste, estuvo, estuvimos, estuvisteis, estuvieron

        HACER: hice, hiciste, hizo, hicimos, hicisteis, hicieron

  TENER: tuve, tuviste, tuvo, tuvimos, tuvisteis, tuvieron

  DECIR: dije, dijiste, dijo, dijimos, dijisteis, dijeron

  HABER: hubo, hubiste, hubo, hubimos, hubisteis, hubieron

SER / IR: fui, fuiste, fué, fuimos, fuisteis, fueron

Note they share form in the past.

Past subjunctive (imperfecto de subjuntivo):

Past simple indicative (indefinido) third person plural (THEY) is taken as the root to conjugate past subjunctive (imperfecto de subjuntivo). All these verbs keep their irregularity patterns:

Ojalá FUERA primavera.

Si ESTUVIERAS más tiempo conmigo, me harías muy feliz.



These Spanish verbs would need a monographic article due to their complexity in use, as, surely, you would have noticed by now. Anyway, roughly speaking (a groso modo) we could say SER defines the person, the being we are, our attributes, characteristics, features, whereas ESTAR defines a state, a condition, a feeling:

SOY una persona bastante tranquila, pero ESTOY muy nerviosa ante esta situación. (I AM a fairly calm person, but I AM very nervous about this situation)

ESTAR also refers to location, place:

¿Dónde estás? Estoy enfrente de tu casa. (Where are you? I am in front of your house.)

ESTAR+ gerund means an action that is taking place right now

Mi hermana está lavando el coche (my sister is washing the car)

Although both are used to form the passive voice, ESTAR is a verb more frequently used as it shows the final result:

El vaso está roto (the glass is broken/has been broken)

Las habitaciones están alquiladas (the rooms are booked / have been booked)


We use this verb to conjugate other verbs in perfect tenses:

¿Has comido en este restaurante? (Have you had lunch at this restaurant?).

HABER DE + infinitive: Its use with an infinitive express ‘necessity’ to do what that infinitive indicates:

He de levantarme temprano mañana por la mañana (I need to get up early tomorrow morning)

Habrás de ir a la oficina de correos (you’ll have to go to the post office)

The impersonal third-person singular form HAY means ‘there is/are’:

No hay leche en la nevera (there isn’t any milk in the fridge)

Habrá tiempo suficiente (there will be enough time)

Hay muchos libros en la mesa (there are many book on the table)

Había muchas razones (there were many reasons)

HAY QUE + infinitive also express ‘necessity’, but in an impersonal way:

Hay que limpiar la sala (the room has to be cleaned)

Hay que tener ilusión (you must have hope, you need hope)


It means ‘can’, with the sense of

‘to be able to’

Yo no puedo leer tan rápido (I can’t /am not able to read so fast)

Don’t get it mixed up with SABER hacer algo, which means ‘to know how to’. Ella no sabe leer todavía (she can’t read, yet)

¿Sabéis nadar? (Can you swim?)

‘to be allowed to’

Los estudiantes no pueden abandonar el centro (the students cannot/are not allowed to leave the facilities)

’to have the right to’

El gobierno no puede obligar a la población (The government can’t force the population)

‘to be possible’, you’ve got the time, the place or the ease to do something,

¿Puedes venir mañana a mi casa? ( Can you come home tomorrow?)

Puedo ayudarte si quieres ( I can help you, if you want to)

It also means ‘might’, ‘may’, when expressing probability:

Puede que llueva mañana (it might rain tomorrow)

Poder also has the idea of ‘to stand’, ‘to put up with’:

No puedo más, dijo la empresa (I can’t stand it any longer, I quit. I can’t go on)

No puede con la injusticia (she can’t stand injustice)


It means ‘to have got’:

Tengo dos hermanos (I’ve got two brothers)


Ten la cuerda por este extremo (hold the rope by this end)

TENER QUE + infinitive means ‘have to’:

Tienes que preparar la cena (you have to cook dinner)

Note we do also use it to experience a feeling like hunger, fear… ‘TENER+ noun is used instead of the English structure TO BE + adjective:

Tengo hambre (I’m hungry)

Tengo frío (I’m cold)

Tengo sueño (I’m sleepy)


It means both ‘to make’ and ‘to do’:

Hizo una tarta de cumpleaños (he made a birthday cake)

Hicimos una fortuna con este negocio (we made a fortune with this business)

Hacen los deberes después de comer (they do their homework after lunch)

It’s impersonal third person singular refers to past time ‘ago’,’for’,’since’:

Vino aquí hace tres años (he came 3 years ago)

Hace 3 años que vive aquí (he’s lived here for 3 years)

Hacía mucho tiempo que no te veía (it was a long time since I last saw you)


It usually means ‘to say’:

Dijo que quería viajar en avión (she said she wanted to travel by plane)

And it means ‘to tell’, ‘to ask’ to express request, orders, or commands in indirect speech:

Nos dijo que cerráramos la puerta (she asked us to close he door)

Mi madre siempre me dice que sea feliz (my mother always tells me to be happy)


It means ‘to work’ in the context of being employed or making an effort:

Ese médico trabaja en el hospital (this doctor works at the hospital)

Trabajé intensamente en ese periodo (I worked hard at that time)

But we do use the Spanish verb ‘FUNCIONAR’ to express ‘to work’ as ‘to function’ or ‘to be useful’:

La cafetera no funciona (the coffee maker doesn’t work)

La vacuna puede funcionar para terminar con esta eterna pandemia (The vaccine can be useful/work to end with this neverending pandemic)


It’s usually used as the modal verb ‘must’:

DEBER + infinitive implies obligation, same as ‘must’ or ‘have to’

Debes presentar el proyecto antes de fin de mes. (You must hand in the project by the end of the month)

DEBER DE + infinitive implies doubt 

No debe de haber mucha gente dispuesta a hacerlo (there must not be a lot of people willing to do it)

It also means ‘to owe’

Está con el agua al cuello pues debe mucho dinero al banco (He’s with the water up to his neck as he owes the bank a lot of money)


It means ‘to go’

Quiero ir al teatro ( I want to go to the theatre)

‘to work’, ‘to function’

La cafetera no va (the coffee maker doesn’t work)

IR A + infinitive, same as ‘to be going to’, to express near future action or an intention

Esta noche vamos a ir al teatro (we’re going to go to the theatre)

Íbamos a viajar a Londres, cuando anunciaron las nuevas restricciones y nos echamos atrás (we were going to travel to London, when they announced the new restrictions and we backed out)

IR + gerund means an action in progress

Voy haciendo la comida (I’ll get to cooking lunch)

IR DE + noun,adjective means ‘to wear’

¿Cómo vas al trabajo? Yo voy de uniforme/yo voy de azul (What do you wear at work? I wear a uniform / I am in blue.

Of course, this is a brief explanation of these more commonly used Spanish verbs, but hopefully, it will help you make some progress.

Puede que seas uno de esos valientes que está haciendo un curso de español, así que tengo que decirte que debes ir a por todas, y que, aunque haya que trabajar duro, sigas con tu proyecto.

You might be one of those brave ones who is taking a Spanish course, so I have to tell you that you must go all out, and, even if you have to work hard, you must keep on with your project.