Spelling: -car, -gar, -zar | Spanish (Latin America) Grammar

Some -ar verbs look regular until you try to build the yo form of the preterite. Because Spanish spelling has to preserve sound as well as grammar, a handful of verb endings force a spelling change in that one form. The good news is the rule is mechanical and the rest of the conjugation is perfectly regular.

Why the Change Happens

In Spanish, the letters c, g, and z behave differently depending on the vowel that follows them:

c before a, o, u is hard (like English k). Before e or i, it becomes soft (like s).
g before a, o, u is hard (like English g in go). Before e or i, it becomes a throat-sound (like Spanish j).
z is almost never written before e in modern Spanish. It becomes c.

The preterite yo ending is -é, which starts with e. That would turn *busqe, *llegé, *empezé into words pronounced in surprising ways. To keep the original sound, Spanish changes the spelling.

The Three Patterns

Ending	Change	yo form
-car	c → qu	busqué (from buscar)
-gar	g → gu	llegué (from llegar)
-zar	z → c	empecé (from empezar)

Only the yo form changes. Every other person keeps the regular spelling.

buscar (-car)

Subject	buscar
yo	busqué
tú	buscaste
él / ella / usted	buscó
nosotros / nosotras	buscamos
ellos / ellas / ustedes	buscaron

Busqué mis llaves por todas partes.

I looked for my keys everywhere.

Toqué el piano durante dos horas.

I played the piano for two hours.

Other common -car verbs: tocar (to touch/play), explicar (to explain), practicar (to practice), sacar (to take out).

llegar (-gar)

Subject	llegar
yo	llegué
tú	llegaste
él / ella / usted	llegó
nosotros / nosotras	llegamos
ellos / ellas / ustedes	llegaron

Llegué tarde a la reunión.

I arrived late to the meeting.

Pagué la cuenta con tarjeta.

I paid the bill with a card.

Other common -gar verbs: pagar (to pay), jugar (to play), apagar (to turn off), entregar (to hand in).

empezar (-zar)

Subject	empezar
yo	empecé
tú	empezaste
él / ella / usted	empezó
nosotros / nosotras	empezamos
ellos / ellas / ustedes	empezaron

Empecé a estudiar a las ocho.

I started studying at eight.

Almorcé en un restaurante nuevo.

I had lunch at a new restaurant.

Other common -zar verbs: almorzar (to have lunch), comenzar (to begin), organizar (to organize), cruzar (to cross).

The Big Picture

The rule is easy to remember when you think of it as sound preservation. The verb buscar has a k sound; we want to keep that k sound in busqué, so we write qu. The verb llegar has a hard g sound; we keep it with gu. The verb empezar has an s sound (in Latin American Spanish); we keep that sound with c.

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This same spelling logic appears across Spanish — in the present subjunctive (busque, llegue, empiece) and in formal commands. Once you understand why the letters change, you can predict it in every tense where a conflicting vowel follows.

Other Forms Stay Regular

Do not overapply this rule. Only the yo form changes. The other forms of these verbs use the original spelling: buscaste, llegó, empezaron. There is no such word as *busqaste or *lleguó.

Tú buscaste y yo busqué.

You searched and I searched.

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A helpful mnemonic: CAR → QUÉ, GAR → GUÉ, ZAR → CÉ. Five seconds of memorization covers dozens of verbs.

Common mistakes

❌ Yo buscé mis llaves toda la mañana.

Wrong: c before é would change the sound to s.

✅ Yo busqué mis llaves toda la mañana.

Correct: c → qu to preserve the hard k sound.

❌ Yo llegé tarde a clase.

Wrong: g before é would produce a soft throat sound.

✅ Yo llegué tarde a clase.

Correct: g → gu to preserve the hard g sound.

❌ Yo empezé a estudiar a las ocho.

Wrong: z before e is avoided in Spanish spelling.

✅ Yo empecé a estudiar a las ocho.

Correct: z → c before e.

❌ Tú busquaste en el closet.

Wrong: the spelling change only affects the yo form.

✅ Tú buscaste en el closet.

Correct: all non-yo forms keep the original spelling.