- A2 Essential: Learn the three types of stem changes: e→ie, o→ue, and e→i
- Understand the "boot pattern" and why nosotros/vosotros don't change
- Recognise which verb forms change based on where the stress falls
- Apply stem changes in present, subjunctive, and imperative tenses
- Learn special preterite rules for e→i verbs (pedir, servir)
- Distinguish between o→ue verbs (regular in preterite) and o→u verbs (dormir, morir)
- Memorise common stem-changing verbs in each category
- Use stem-changing verbs correctly in everyday conversation
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Essential VerbsElementary
Stem-Changing Verbs
Learn the 'Boot Verbs' (e→ie, o→ue, e→i)
What You'll Learn
Overview
Stem-changing verbs (also called "boot verbs" because of their shape in conjugation tables) are Spanish verbs that change their stem vowel in certain conjugations. This is a uniquely Spanish concept that doesn't exist in English!
There are three main types of stem changes in present tense. These patterns help you predict how hundreds of Spanish verbs behave:
- e→ie (like querer - "to want")
- o→ue (like poder - "can/to be able to")
- e→i (like pedir - "to ask for")
Why Spanish Has Stem Changes
English verbs stay the same in their stem: "I want, you want, he wants" - the "want" part never changes. Spanish developed differently, creating internal vowel changes for emphasis and clarity.
The Boot Pattern (Present Tense)
In the present tense, the stem change happens in yo, tú, él, ellos but NOT in nosotros, vosotros. When you draw a line around the changing forms in a conjugation table, it looks like a boot! 👢
| Person | QUERER (e→ie) - Present Tense | |
|---|---|---|
| Singular | Plural | |
| 1st (I/We) | quiero | queremos |
| 2nd (You) | quieres | queréis |
| 3rd (He/She/They) | quiere | quieren |
The red border shows the "boot" shape - these are the forms where the stem changes!
Structure & Formation
The Three Types of Stem Changes
Each stem-changing verb follows one of three patterns in the present tense. The changes follow the "boot pattern" - they occur in yo, tú, él/ella, ellos/ellas but NOT in nosotros, vosotros (because the stress falls on a different syllable).
Present Tense
QUERER (e→ie)
| Person | Singular | Plural |
|---|---|---|
| 1st | quiero | queremos |
| 2nd | quieres | queréis |
| 3rd | quiere | quieren |
PODER (o→ue)
| Person | Singular | Plural |
|---|---|---|
| 1st | puedo | podemos |
| 2nd | puedes | podéis |
| 3rd | puede | pueden |
PEDIR (e→i)
| Person | Singular | Plural |
|---|---|---|
| 1st | pido | pedimos |
| 2nd | pides | pedís |
| 3rd | pide | piden |
Present Subjunctive
QUERER (e→ie)
| Person | Singular | Plural |
|---|---|---|
| 1st | quiera | queramos |
| 2nd | quieras | queráis |
| 3rd | quiera | quieran |
PODER (o→ue)
| Person | Singular | Plural |
|---|---|---|
| 1st | pueda | podamos |
| 2nd | puedas | podáis |
| 3rd | pueda | puedan |
PEDIR (e→i)
| Person | Singular | Plural |
|---|---|---|
| 1st | pida | pidamos |
| 2nd | pidas | pidáis |
| 3rd | pida | pidan |
Preterite (Special Cases)
PEDIR (e→i)
| Person | Singular | Plural |
|---|---|---|
| 1st | pedí | pedimos |
| 2nd | pediste | pedisteis |
| 3rd | pidió | pidieron |
SERVIR (e→i)
| Person | Singular | Plural |
|---|---|---|
| 1st | serví | servimos |
| 2nd | serviste | servisteis |
| 3rd | sirvió | sirvieron |
DORMIR (o→u)
| Person | Singular | Plural |
|---|---|---|
| 1st | dormí | dormimos |
| 2nd | dormiste | dormisteis |
| 3rd | durmió | durmieron |
Present Tense - Stem Changes in Action
Present Subjunctive - Same Boot Pattern
| Person | QUERER (e→ie) | PODER (o→ue) | PEDIR (e→i) | |||
|---|---|---|---|---|---|---|
| Singular | Plural | Singular | Plural | Singular | Plural | |
| 1st (I/We) | quiera | queramos | pueda | podamos | pida | pidamos |
| 2nd (You) | quieras | queráis | puedas | podáis | pidas | pidáis |
| 3rd (He/She/They) | quiera | quieran | pueda | puedan | pida | pidan |
Preterite Tense - Special e→i and o→u Patterns (3rd Person Only)
When do these patterns apply?
All three types (e→ie, o→ue, e→i) follow the same boot pattern in:
- Present Indicative - shown above
- Present Subjunctive - same boot pattern (yo, tú, él, ellos)
- Imperative - tú, él/ella, ellos/ellas forms
Common e→ie verbs: pensar (think), empezar (begin), cerrar (close), entender (understand), preferir (prefer), sentir (feel)
Common o→ue verbs: dormir (sleep), volver (return), encontrar (find), recordar (remember), costar (cost), mostrar (show), morir (die)
Common e→i verbs: servir (serve), repetir (repeat), seguir (follow), conseguir (get), vestir (dress), reír (laugh), elegir (choose)
Important: Preterite is different!
Only certain stem-changing verbs have changes in preterite:
- e→i verbs (like pedir, servir): Change e→i in él/ella and ellos/ellas forms ONLY
- o→u verbs (ONLY dormir, morir): Change o→u in él/ella and ellos/ellas forms ONLY
- e→ie and o→ue verbs: Completely regular in preterite (quise, pude, encontré - no stem change!)
Why doesn't "encontrar" change in preterite? It's an o→ue verb (encuentro), not an o→u verb. Only dormir and morir are o→u verbs and change in preterite.
Key Patterns to Remember
- Boot pattern: Changes occur in yo, tú, él, ellos forms (where stress falls on the stem)
- e→i verbs are special: They also change in preterite (3rd person) and throughout imperfect subjunctive
- Gerunds: e→i and o→u verbs change in gerund (pidiendo, durmiendo)
- No changes: Imperfect, future, conditional are always regular for stem-changing verbs
Examples
Real-Life Examples
e→ie
Present
Quiero café.
I want coffee.
Present
¿Piensas mucho?
Do you think a lot?
Present
La clase empieza a las 9.
Class begins at 9.
Imperative
Cierra la puerta.
Close the door.
Subjunctive
Espero que quieras venir.
I hope you want to come.
o→ue
Present
Puedo ayudar.
I can help.
Present
Duermo 8 horas.
I sleep 8 hours.
Present
Vuelvo mañana.
I return tomorrow.
Imperative
Vuelve pronto.
Come back soon.
Preterite
Durmió bien.
He/She slept well.
e→i
Present
Pido un favor.
I ask for a favour.
Present
Sirvo la cena.
I serve dinner.
Imperative
Repite, por favor.
Repeat, please.
Preterite
Pidió ayuda.
He asked for help.
Subjunctive
Espero que sirvas bien.
I hope you serve well.
Common Mistakes
Common Mistakes & Tips
Don't Change Nosotros/Vosotros Forms
Wrong: Nosotros quieremos
Correct: Nosotros queremos
Remember the boot pattern - nosotros and vosotros stay outside the boot!
Memory Tip: Stress = Change
The stem change happens when the stem is stressed:
QUIER-o (stressed, changes) vs. que-RE-mos (unstressed, no change)
Quick Test
Question 1
What type of stem change does 'querer' have?
Question 2
Complete: 'Nosotros _____ (poder) ayudar'
Question 3
Which forms of stem-changing verbs DON'T change?
Question 4
Complete: 'Tú _____ (dormir) mucho'
Question 5
What type of change does 'pedir' have?
Question 6
Which tenses have stem changes for e→ie and o→ue verbs?
Want more practice? Try our interactive fill-in-the-blank exercises.