Forming the Past Tense: the l-participle

The Czech past tense is built from two pieces: an l-participle (a form of the main verb ending in -l) and the present tense of být ("to be") used as an auxiliary. There is only one past tense for everyday purposes — the same construction covers "I did," "I was doing," and "I have done," with aspect (not a separate tense) handling the difference. This page is a reference for assembling it correctly: the participle endings, their agreement, and the all-important placement of the auxiliary.

The two ingredients

1. The l-participle — take the past stem and add an -l plus a gender/number ending. For most verbs the past stem is the infinitive minus -t:

• dělat → dělal
• být → byl
• vidět → viděl

2. The auxiliary být — the present-tense forms jsem, jsi, jsme, jste mark first and second person. Crucially, the third person has no auxiliary at all — the bare participle stands alone.

Gender and number agreement

This is what English speakers most need to internalize: the participle agrees with the subject in gender and number, exactly like an adjective. The choice of ending depends on whether the subject is masculine, feminine, or neuter, singular or plural — and in the plural, on animacy for masculines.

Singular

Plural

The endings -li, -ly, -la are pronounced identically in casual speech but written differently — this is one of the trickiest spelling distinctions in Czech and a constant headache even for natives. See l-participle agreement.

The masculine-animate -li vs. feminine -ly contrast

The plural is where agreement bites hardest. A group of men (or any group including at least one man, with a masculine-animate head noun) takes -li; a group of women, or masculine-inanimate things, takes -ly.

For mixed-gender groups (men and women together), the masculine-animate -li wins. See l-participle agreement.

Consonant-stem participles without -e-

Many common verbs whose stem ends in a consonant form the participle without an inserted -e- before the -l. You cannot say neselo with an extra vowel — the consonant sits directly against the -l:

The -nul / -l split for -nout verbs

Verbs ending in -nout have two competing participle shapes. The older, fuller form keeps -nu- (tisknul); the shorter, often more literary or standard form drops it (tiskl). Both are heard; the choice varies by verb and register, with the shorter form felt as more formal for many verbs and the -nul form as more colloquial.

A handful of -nout verbs sit outside this neat split because their standard participle uses a different stem altogether — most notably zapomenout ("to forget"), whose standard past is zapomněl (the zapomnul you sometimes hear is colloquial).

The auxiliary is a second-position clitic

This is the rule that makes Czech past-tense word order feel alien at first. The auxiliary jsem / jsi / jsme / jste is a clitic: an unstressed little word that must sit in the second position of the clause — right after the first stressed unit, not necessarily next to its participle. If the participle is the first word, the auxiliary follows it; but if anything else opens the clause (an adverb, an object, a subject), the auxiliary slots in immediately after that opener.

When several clitics cluster, they line up in a fixed order — the auxiliary first, then short-form pronouns. See the clitic second-position rule and the past-tense auxiliary.

Common mistakes