1. Stem-Changing –AR Verbs
Let’s give them the boot!

2. We already know our subject
pronouns …
nosotros
yo
nosotras
vosotros
tú
vosotras
él ellos
ella ellas
Ud. Uds.

3. … and we already know our –AR verb
endings …
-o -amos
-as -áis
-a -an

4. So what else do we need to know
about the present tense of –AR verbs?
• Some –AR verbs are regular stem-changing
verbs. Sometimes they are called “boot”
verbs. You will see why very soon.
• There are two categories of regular stem-
changing –AR verbs, o to ue and e to ie.
• There are three rules that apply to these stem-
changing verbs.

5. The Three Rules
1. The stem change occurs in all forms except
nosotros and vosotros.
2. The stem change occurs in the syllable
directly before the verb ending.
3. The verbs have regular endings in the present
tense.

6. Let’s try one together.
• We are going to start with an o to ue–AR verb,
contar (ue): to count, to tell.
• Rule 1 says that the stem change will occur in all
forms except nosotros and vosotros, so we know
that those will be contamos and contáis.
• Rule 2 says that the stem change will occur in the
syllable directly before the verb ending, in this
case it is the only o.
• Rule 3 says the endings will be regular.
• Let’s put this together in a chart.

7. contar (ue): to count, to tell
• yocuento • nosotros/as contamos
• túcuentas • vosotros/as contáis
• élcuenta • elloscuentan
• ellacuenta • ellascuentan
• Ud. cuenta • Uds. cuentan

8. So, what does this have to do with a
boot?
• yocuento • nosotros/as contamos
• túcuentas • vosotros/as contáis
• élcuenta • elloscuentan
• ellacuenta • ellascuentan
• Ud. cuenta • Uds. cuentan

9. First, let’s X out the forms that don’t
have a stem change.
• yocuento X • nosotros/as contamos
• túcuentas X • vosotros/as contáis
• élcuenta • elloscuentan
• ellacuenta • ellascuentan
• Ud. cuenta • Uds. cuentan

10. Then, let’s “circle” the forms that do
have a stem change.
• yocuento X • nosotros/as contamos
• túcuentas X • vosotros/as contáis
• élcuenta • elloscuentan
• ellacuenta • ellascuentan
• Ud. cuenta • Uds. cuentan

11. Alright, it is not a perfect boot.
• yocuento X • nosotros/as contamos
• túcuentas X • vosotros/as contáis
• élcuenta • elloscuentan
• ellacuenta • ellascuentan
• Ud. cuenta • Uds. cuentan

12. Here is a list of common –AR o to
uestem-changing verbs.
• almorzar (ue): to eat lunch
• contar (ue): to count, to tell
• costar (ue): to cost
• encontrar (ue): to find, to meet
• mostrar (ue): to show
• recordar (ue): to remember
• sonar (ue): to sound, to ring
• volar (ue): tofly
• jugar (ue): to play*

13. Wait. Did you see that last verb?
jugar (ue): to play
It’s an irregular stem-changing verb,
but it still honors the boot.
• yojuego • nosotrosjugamos
• tújuegas • vosotrosjugáis
• éljuega • ellosjuegan

14. Take note!!!
• If it’s in the boot, change the root!
• When stem-changing verbs are listed in a
glossary, they will indicate the change. (ue)
indicates the stem change of o to ue.

15. Let’s try another one together.
• We are going to try an e to ie–AR verb, cerrar (ie):
to close.
• Rule 1 says that the stem change will occur in all
forms except nosotros and vosotros, so we know
that those will be cerramos and cerráis.
• Rule 2 says that the stem change will occur in the
syllable directly before the verb ending, in this
case it is the only e.
• Rule 3 says the endings will be regular.
• Let’s put this together in a chart.

16. If it’s in the boot, change the root!
cerrar (ie): to close
• yocierro X • nosotros/as cerramos
• túcierras X • vosotros/as cerráis
• élcierra • elloscierran
• ellacierra • ellascierran
• Ud. cierra • Uds. cierran

17. Here’s a list of common –AR e to
iestem-changing verbs.
• cerrar (ie): to close
• comenzar (ie): to begin
• confesar (ie): to confess
• empezar (ie): to begin
• pensar (ie): to think

18. Take note!!!
• If it’s in the boot, change the root!
• When stem-changing verbs are listed in a
glossary, they will indicate the change.
– (ue) indicates the stem change of o to ue.
– (ie) indicates the stem change of e to ie.

19. Can you translate the following
sentences into Spanish?
• He closes the door.
• Élcierra la puerta.
• We begin the class.
• Nosotrosempezamos la clase.
• They think about the family.
• Ellaspiensan en la familia.
• Do you close the windows?
• ¿Cierrastúlasventanas?

20. Can you translate the following
sentences into Spanish?
• We eat lunch in Lak Dining Hall.
• Nosotrosalmorzamos en Lak Dining Hall.
• He finds my mother.
• Élencuentra a mi madre.
• They show the books.
• Ellosmuestran los libros.
• How much does the pen cost?
• ¿Cuántocuesta la pluma?

22. almorzar (ue): to eat lunch
• yoalmuerzo • nosotros/as almorzamos
• túalmuerzas • vosotros/as almorzáis
• élalmuerza • ellosalmuerzan
• ellaalmuerza • ellasalmuerzan
• Ud. calmuerza • Uds. almuerzan