Conhecer

Conhecer covers two ideas English keeps apart: to know in the sense of being acquainted with a person, place, or thing, and to meet someone for the first time. It is an -er verb that is regular in sound but has one spelling change: the c becomes ç in the forms where it would otherwise sit before o or a — namely the first-person singular present (conheço) and the entire present subjunctive (conheça, conheças, conheça, conheçamos, conheçam). Everywhere else it keeps a plain c. This page gives the full paradigm and then the all-important contrast with saber.

Why the ç appears

Just like in começar, the cedilla exists to preserve the soft /s/ sound. The stem conhec- is pronounced with a final /s/; that /s/ is spelled c before e and i (conhece, conhecemos), but to keep the same sound before o and a it must be spelled ç (conheço, conheça). So the change is mechanical: whenever an ending starting with o or a attaches to this stem, write ç.

Presente do indicativo

Only the eu form takes the cedilla, because only it has the ending -o. The rest keep a plain c.

Pretérito perfeito

The preterite endings all begin with vowels other than o/a in the relevant positions, so the c stays plain. The first-person conheci very often means I met (made someone's acquaintance for the first time).

Pretérito imperfeito

The imperfect of -er verbs uses -ia, so no cedilla. Use it for "used to know / was acquainted with."

Futuro do presente & futuro do pretérito (conditional)

Both are built on the full infinitive conhecer-, which already contains a plain c — no spelling change occurs.

In speech, the simple future is replaced by ir + infinitive: vou conhecer rather than conhecerei. (informal)

Presente do subjuntivo

This is the other place the cedilla appears: the whole present subjunctive, because -er verbs take -a endings here, all starting with a.

Imperfeito & futuro do subjuntivo

The imperfect subjunctive (-esse) and future subjunctive (built on the preterite stem) both keep a plain c.

Imperativo

The cedilla appears in the você and vocês commands (from the subjunctive) and the nós command, but not in the affirmative tu form conhece (which comes from the present indicative and ends in -e).

Non-finite forms

conhecer vs. saber — the key distinction

English has only one verb, to know. Portuguese splits it in two, and choosing wrong is one of the most common beginner errors.

• conhecer = to be acquainted with — used for people, places, and things you experience directly. It implies familiarity gained through contact. It cannot take a clause as its object.
• saber = to know a fact, piece of information, or how to do something — used with facts, with embedded questions (saber que, saber onde, saber se), and with abilities (saber nadar = know how to swim).

The clearest rule of thumb: if the object is a noun (a person, a city, a song, a book), use conhecer. If the object is a fact, a "that/whether/where" clause, or an infinitive of ability, use saber. See the dedicated saber vs. conhecer page for the full treatment.

Common Mistakes

Key Takeaways

• The cedilla appears only in conheço (present eu) and the present subjunctive conheça / conheçam; everywhere else the c stays plain.
• In the preterite, conheci usually means I met someone for the first time.
• Use conhecer for people/places/things; use saber for facts, clauses, and abilities.