Stem-changing verbs

Gramática II, Unidad 6

Present tense of stem-changing verbs

 

A few simple things to begin:

  • How do when know if a verb stem changes? Easy. Our course site tells us. Otherwise, we'd have no way of knowing.
     
  • How do we know what kind of stem change a verb has? Again, easy. The course site also gives us that information.
     
  • Once you're told, though, it's your responsibility to remember which verbs have which kinds of stem changes.

The basics: conjugating e to ie stem changing verbs in the present tense.

Remember, with stem-changing verbs, what makes them special is that, instead of leaving the stem alone after we derive it (by removing the -AR, -ER or -IR infinitive ending), whenever the subject is NOT nosotros (or vosotros, but we won't use vosotros-forms in this course), we change the stem vowel in a certain way.

Once that change is made, then we add the right conjugated ending for the sentence's subject.

As always, when conjugating, we're only concerned with 2 things: 

  • stem  
  • ending

For regular stem-changing verbs, the only form that doesn't show a stem change is the nosotros-form:

infinitive: pensar

nosotros-form: pensamos

conjugated ending is "amos"

infinitive: querer

nosotros-form: queremos

conjugated ending is "emos"

infinitive: preferir

nosotros-form: preferimos

conjugated ending is "imos"

infinitive: empezar

nosotros-form: empezamos

conjugated ending is "amos"

infinitive: perder

nosotros-form: perdemos

conjugated ending is "emos"

infinitive: entender

nosotros-form: entendemos

conjugated ending is "emos"

In the other 4 present-tense forms, the stem "e" has to change to an "ie" before we can add a conjugated ending.

Once that change is made, then we add the right conjugated ending for the sentence's subject.

The 4 forms of new -AR verb "pensar" where the stem "e" changes to "ie" are:

tú form: piensas
changed stem is "piens"

conjugated ending is "as"

3rd-person singular: piensa
changed stem is "piens"

conjugated ending is "a"

3rd person plural: piensan
changed stem is "piens"

conjugated ending is "an"

yo form: pienso
changed stem is "piens"

conjugated ending is "o"

The 4 forms of new -ER verb "perder" where the stem "e" changes to "ie" are:

tú form: pierdes
changed stem is "pierd"

conjugated ending is "es"

3rd-person singular: pierde
changed stem is "pierd"

conjugated ending is "e"

3rd person plural: pierden
changed stem is "pierd"

conjugated ending is "en"

yo form: pierdo
changed stem is "pierd"

conjugated ending is "o"

There are 2 other types of stem changes in the language:
e to i and o to ue (which has a subtype, u to ue, which is very uncommon).

We'll look at the o to ue stem change now.

  • As always, the nosotros-form shows no stem change. Let's take our new verb "poder".
     
  • Its nosotros-form starts with the unchanged stem "pod"
     
  • To this unchanged stem, we add the nosotros-form ending "emos" (because this is an -ER verb)
     
  • That gives us the present-tense nosotros-form "podemos"
     
  • Easy! It's just stem plus ending, like all present-tense conjugation.

The 4 forms of new -ER verb "poder" where the stem "o" changes to "ue" are:

tú form: puedes
changed stem is "pued"

conjugated ending is "es"

3rd-person singular: puede
changed stem is "pued"

conjugated ending is "e"

3rd person plural: pueden
changed stem is "pued"

conjugated ending is "en"

yo form: puedo
changed stem is "pued"

conjugated ending is "o"

Let's try a few conjugations with our new verbs (all can be found in the Resumen Gramatical in the Gramática II section of Unidad 6):
 

  • Los chicos____________(soñar) [stem changes o to ue]
     
  • Tú ___________(jugar) [stem changes u to ue]
     
  • Yo ____________(entender) [stem changes e to ie]
     
  • Mi hija ___________(servir) [stem changes e to i]

 

SOÑAR

  • Los chicos ____________(soñar) [stem changes o to ue]
     
  • step 1: derive the stem: soñ
     
  • step 2: will the stem change? yes
     
  • step 3: change the stem: sueñ
     
  • step 4: add conjugated ending "an" for 3rd-person plural subject "los chicos"
     
  • step 5: success! "sueñ" + "an"="sueñan", the correct form.

 

JUGAR

  • Tú ___________(jugar) [stem changes u to ue]
     
  • step 1: derive the stem: jug
     
  • step 2: will the stem change? yes
     
  • step 3: change the stem: jueg
     
  • step 4: add conjugated ending "as" for subject "tú"
     
  • step 5: success! "jueg" + "as"="juegas", the correct form.

 

ENTENDER

  • Yo ____________(entender) [stem changes e to ie]

     
  • step 1: derive the stem: entend
     
  • step 2: will the stem change? yes
     
  • step 3: change the stem: entiend
     
  • step 4: add conjugated ending "o" for subject "yo"
     
  • step 5: success! "entiend" + "o"="entiendo", the correct form.

 

SERVIR

  • Mi hija ___________(servir) [stem changes e to i]
     
  • step 1: derive the stem: serv
     
  • step 2: will the stem change? yes
     
  • step 3: change the stem: sirv
     
  • step 4: add conjugated ending "e" for 3rd-person-singular subject "mi hija"
     
  • step 5: success! "sirv" + "e"="sirve", the correct form.

 

EXAM-FORMAT PRACTICE

For every blank in the exam, you will have to do two things:

  • First, choose the correct verb for meaning.
  • Second, conjugate the verb you choose in the present tense for its subject.
     
  • La clase ____________(entender/empezar) a las dos de la tarde.
     
  • Yo ____________(soñar/pensar) con volver a Chile.
     
  • ¿Ustedes ___________(preferir/contar) estudiar en casa o en la biblioteca?
     
  • Los estudiantes ____________(repetir/poder) las palabras nuevas.
     
  • Pablo y yo ___________(querer/sonreír) viajar a Dinamarca.

Remember--for every blank in the exam, you must do two things:

  • First, choose the correct verb for meaning.
  • Second, conjugate the verb you choose in the present tense for its subject.
     
  • La clase ________(entender/empezar) a las dos de la tarde.
  • empezar
  • empieza
     
  • Yo _______(soñar/pensar) con volver a Chile.
  • soñar
  • sueño
     
  • ¿Ustedes ________(preferir/contar) estudiar en casa o en la biblioteca?
  • preferir
  • prefieren

Remember--for every blank in the exam, you must do two things:

  • First, choose the correct verb for meaning.
  • Second, conjugate the verb you choose in the present tense for its subject.
     
  • Los estudiantes ______(repetir/poder) las palabras nuevas.
  • repetir
  • repiten
     
  • Pablo y yo ________(querer/sonreír) viajar a Dinamarca.
  • querer
  • queremos