Spanish present tense consonant change c > zc in -cer/-cir verbs

In Spanish, the  -c changes to a -zc in El Presente for many verbs that end in -cer/-cir that are preceded by a vowel. This only affects the yo form. Have a look at these two verbs conjugations in El Presente.

 Vowel+CER verb 

CONOCER
(to meet/know)

yo

conozco

conoces

él / ella / usted

conoce

nosotros/nosotras

conocemos

vosotros/vosotras

conocéis

ellos/ellas/ustedes

conocen



 Vowel+CIR verb 

PRODUCIR
(to produce)

yo

produzco

produces

él /ella/usted

produce

nosotros/nosotras

producimos

vosotros/vosotras

producís

ellos/ellas/ustedes

producen


Note that common verbs hacer (to do/make) and decir (to say) do not have this type of irregularity! They are still irregular though, see Verbos yo-go (presente).

For other verbs within this same irregularity see:

Want to make sure your Spanish sounds confident? We’ll map your knowledge and give you free lessons to focus on your gaps and mistakes. Start your Braimap today »

Learn more about these related Spanish grammar topics

Examples and resources

Esa fábrica produce mucho plástico.That factory produces a lot of plastic.
¿Tú conoces a mi amiga Marta?Do you know my friend Marta?
Ellos no conocen a la novia de Miguel.They don't know Miguel´s girlfriend.
Yo conozco a David Martínez.I know David Martínez.
Nosotros no conocemos a mucha gente en este pueblo.We don't know many people in this village.
¿Vosotros producís aceite de oliva virgen?Do you produce virgin olive oil?
Let me take a look at that...