I-Class Conjugation in Czech

In Brief

A common Czech present-tense pattern uses the endings -ím, -íš, -í, -íme, -íte, -í: mluvím “I speak,” mluvíš “you speak,” mluví “he, she, or they speak.” The ending usually makes the subject clear, so Czech often leaves out words such as já “I” and ty “you.” Learn each new verb with its first-person form, because the infinitive alone does not always reveal its present-tense pattern.

Overview

The I-class pattern is one of the main ways Czech verbs form the present tense. In this article, I-class means the learner-friendly pattern whose first two forms end in -ím and -íš. It includes very useful verbs such as mluvit “to speak,” vidět “to see,” prosit “to ask or request,” and slyšet “to hear.” You will meet it early at A1 because it lets you talk about languages, everyday activities, perceptions, requests, and abilities.

A verb changes its ending according to its subject (the person or thing performing the action). English makes only a small change in “I speak” versus “she speaks,” but Czech uses a different ending for each grammatical person: speaker, listener, or someone else. Singular means one person or thing; plural means more than one.

Czech usually does not need an explicit subject pronoun. Mluvím česky already means “I speak Czech,” because -ím identifies the speaker. Pronouns remain useful for contrast—Já mluvím česky, ale on mluví polsky (“I speak Czech, but he speaks Polish”)—but repeating them in every sentence sounds heavier than natural Czech.

How It Works

The core endings

The infinitive is the dictionary form translated with English “to,” such as mluvit “to speak.” To conjugate a regular verb of this pattern, use its present stem (the stable part carrying the main meaning) and add the following endings:

Person	Czech pronoun	Ending	mluvit “to speak”
1st person singular	já	-ím	(já) mluvím
2nd person singular	ty	-íš	(ty) mluvíš
3rd person singular	on / ona / ono	-í	(on/ona/ono) mluví
1st person plural	my	-íme	(my) mluvíme
2nd person plural	vy	-íte	(vy) mluvíte
3rd person plural	oni / ony / ona	-í	(oni/ony/ona) mluví

Two details are especially important:

1. The long vowels marked by accents are part of the spelling: í in mluvím and íš in mluvíš cannot be omitted.
2. The third-person singular and plural forms are identical: mluví can mean “he speaks,” “she speaks,” “it speaks,” or “they speak.” Context or an explicit subject tells you which meaning is intended.

Four useful model verbs

The same set of endings appears with verbs whose infinitives look different:

Person	mluvit “speak”	vidět “see”	prosit “ask”	slyšet “hear”
já	mluvím	vidím	prosím	slyším
ty	mluvíš	vidíš	prosíš	slyšíš
on/ona/ono	mluví	vidí	prosí	slyší
my	mluvíme	vidíme	prosíme	slyšíme
vy	mluvíte	vidíte	prosíte	slyšíte
oni/ony/ona	mluví	vidí	prosí	slyší

With many verbs ending in -it, removing -it gives a useful working stem: mluv-it → mluv-, pros-it → pros- and uč-it → uč-. Several common verbs in -ět or -et also follow the pattern: vidět → vidím, rozumět → rozumím (“understand”), slyšet → slyším, and sedět → sedím (“sit”).

This is a practical guide, not a rule for guessing every Czech verb. Infinitives with similar endings may conjugate differently, and some I-class verbs have an unexpected-looking infinitive. Learn a new verb as a pair—ideally infinitive + já form: mluvit — mluvím, vidět — vidím, spát — spím.

Questions and negative forms

A yes/no question normally keeps the same verb form. In speech, intonation marks the question; in writing, the question mark makes it clear:

• Mluvíš česky. — “You speak Czech.”
• Mluvíš česky? — “Do you speak Czech?”

English adds “do” in many present-tense questions, but Czech does not. Question words can come before the verb: Co vidíš? (“What do you see?”), Koho prosíte o pomoc? (“Whom are you asking for help?”).

For a negative statement, attach ne- directly to the verb:

Positive	Negative	Meaning
mluvím	nemluvím	I do not speak / I am not speaking
vidíš	nevidíš	you do not see / you cannot see
slyšíme	neslyšíme	we do not hear / we cannot hear
rozumíte	nerozumíte	you do not understand

Do not write ne as a separate word. Czech treats it as part of the verb in these forms.

One Czech present, two common English translations

English distinguishes “I speak” from “I am speaking.” Czech normally uses the same present form for both:

• Mluvím česky. — “I speak Czech.”
• Teď mluvím s lékařem. — “I am speaking with the doctor now.”

Time words and context supply the distinction. Do not look for a separate Czech equivalent of English “am” in a sentence such as “I am speaking.”

Examples in Context

Czech	English	Note
Mluvím česky.	I speak Czech.	First-person singular; no pronoun needed.
Mluvíš anglicky?	Do you speak English?	A yes/no question without an equivalent of English “do.”
Petr mluví velmi rychle.	Petr speaks very quickly.	The noun Petr identifies the subject.
Doma mluvíme česky.	We speak Czech at home.	First-person plural.
Mluvíte německy?	Do you speak German?	Can address one person formally or several people.
Vidíš to?	Do you see it?	Second-person singular, informal.
Z okna vidím řeku.	I can see the river from the window.	English often uses “can see”; Czech needs only vidím.
Nic nevidíme.	We cannot see anything.	Negative verb; Czech also uses the negative word nic.
Prosíme o pomoc.	We are asking for help.	prosit o introduces the requested thing.
Prosím, mluvte pomaleji.	Please speak more slowly.	Prosím also works as the everyday word “please.”
Slyšíte mě?	Can you hear me?	Formal singular or plural you.
Slyší nás.	They hear us.	Context supplies the omitted plural subject; the same form can also be singular.
Rozumím vám.	I understand you.	vám can be formal singular or plural.
Každý večer vaříme večeři.	We cook dinner every evening.	vařit — vařím follows the same ending set.
Učím se česky každý den.	I study Czech every day.	The reflexive word se belongs with učit se.

Common Mistakes

Leaving the verb in the infinitive

• Wrong: Já mluvit česky.
• Right: Mluvím česky.
• Why: A normal present-tense statement needs a conjugated verb. Mluvit is only the dictionary form; -ím marks “I.”

Using the first-person ending with ty

• Wrong: Ty mluvím anglicky?
• Right: Mluvíš anglicky?
• Why: Informal singular “you” takes -íš, not -ím. The pronoun ty is usually unnecessary unless you are contrasting people.

Inventing a separate third-person plural ending

• Wrong: Oni mluvíjí česky.
• Right: Oni mluví česky.
• Why: In this pattern, both third-person singular and third-person plural end in -í. There is no -íjí ending.

Separating the negative prefix

• Wrong: Ne mluvím česky.
• Right: Nemluvím česky.
• Why: ne- is attached directly to a finite verb (a verb form that shows person): nevidím, neslyšíš, nerozumíme.

Adding an English-style question helper

• Wrong: Děláš mluvíš česky?
• Right: Mluvíš česky?
• Why: Czech does not use a helper equivalent to English “do” in this question. The conjugated verb and question intonation are enough.

Guessing from the infinitive alone

• Wrong strategy: assuming every verb in -it, -et, or -ět must follow this table.
• Better strategy: learn infinitive + já + oni: mluvit — mluvím — mluví.
• Why: The pattern is common, but Czech infinitives do not always identify the present stem reliably. Common irregular verbs need to be learned separately.

Usage Notes

Informal ty and formal or plural vy

Use ty + -íš with one friend, family member, child, or another person you address informally. Use vy + -íte for several people and when addressing one person formally:

• Slyšíš mě, Petro? — “Can you hear me, Petra?” (informal)
• Slyšíte mě, pane Nováku? — “Can you hear me, Mr Novák?” (formal)
• Slyšíte mě, děti? — “Can you hear me, children?” (plural)

In respectful letters and personal messages, Czech may capitalize Vy and related forms. Capitalization does not change the verb ending.

Prosím is more than “I ask”

As a normal verb, prosit can take a person and a request: Prosím kolegu o pomoc (“I am asking my colleague for help”). Here kolegu is the direct object (the person directly affected by the request), and o pomoc states what is requested.

The standalone form prosím is also extremely common in polite interaction. Depending on context and intonation, it can mean “please,” “here you are,” “pardon?” or “you’re welcome.” It is still historically the first-person form, but beginners can also learn it as a complete everyday expression.

Verbs come with their own sentence patterns

Correct conjugation is only part of learning a verb. Notice the words and prepositions that accompany it:

• mluvit česky — to speak Czech
• mluvit s někým — to speak with someone
• mluvit o něčem — to speak about something
• prosit někoho o něco — to ask someone for something
• rozumět někomu / něčemu — to understand someone or something
• vidět / slyšet někoho / něco — to see or hear someone or something

These patterns involve Czech cases (changes to a noun or pronoun according to its job in the sentence). You do not need to master every case before using the verbs, but it is worth memorizing a short model phrase with each one.

Beyond the Basics / Advanced Use

You do not need to master the following points at A1, but they explain forms you will encounter later.

Present-looking forms can refer to the future

Czech verbs have aspect, meaning that a verb presents an action either as an ongoing/repeated process or as one bounded, completed event. The basic verbs in this lesson are mostly imperfective (process-focused), so mluvím and prosím normally refer to the present.

A related perfective verb (completion-focused) can use the same personal endings but refer to the future:

Imperfective present	Perfective future	Typical meaning
vidím	uvidím	I see / I will see
prosím	poprosím	I ask / I will ask
učím se	naučím se	I am learning / I will learn successfully

This is not a new ending table; it is an interaction between present-tense endings and verbal aspect. For now, learn prefixed verbs such as uvidět or poprosit as separate vocabulary items rather than assuming every prefix produces the same meaning.

Some stems alternate in related forms

The present stem may not stay unchanged elsewhere in the verb system. Commands and past forms can reveal alternations: prosit — prosím — pros! (“ask!”), but učit — učím — uč! (“teach!”), and other verbs have less transparent forms. This is another reason to store several useful forms rather than building every form directly from the infinitive.

The subject can remain ambiguous on purpose

Because third-person singular and plural both end in -í, Bydlí v Praze can mean “He lives in Prague,” “She lives in Prague,” or “They live in Prague.” Czech speakers rely on the previous conversation. They add on, ona, or oni only when clarification or contrast is needed. English normally forces you to choose a subject pronoun, so leaving it unstated may feel unusual at first.

Practice Tips

1. Learn verbs in three-part sets. Record the infinitive, the já form, and the oni form: slyšet — slyším — slyší. This confirms both the stem and the conjugation pattern.
2. Run a six-person drill with one real sentence. Start with Mluvím česky and change it through mluvíš, mluví, mluvíme, mluvíte, mluví. Then repeat with vidět, prosit, and slyšet.
3. Practice English contrasts that Czech combines. Pair “I speak Czech” and “I am speaking Czech now” with Mluvím česky and Teď mluvím česky. This helps you stop searching for an unnecessary equivalent of English “am.”

Related Concepts

• Prerequisite: Personal Pronouns — review já, ty, on/ona, my, vy, and oni before matching them to verb endings.
• Next step: Question Formation — use conjugated verbs in yes/no questions and with words such as co, kdo, and proč.
• Next step: Modal Verbs — combine forms such as musím, umíš, and chceme with another verb in the infinitive.