když
Temporal and Conditional Když
Když is one of the most common Czech conjunctions. It means when (for past, present, and repeated actions) or if (for real, possible conditions).
How It Works
Here is how to use když correctly:
1. Temporal 'When' (Past, Present, Habitual)
Use když to talk about things that happened in the past, happen generally, or happen repeatedly.
- Když jsem byl malý... (When I was little...)
- Když prší, zůstávám doma. (When/Whenever it rains, I stay home.)
Crucial rule: Never use když to mean 'when' for a single, specific future event. For 'When I arrive tomorrow', you must use až.
2. Conditional 'If' (Real Conditions)
Když is frequently used to mean 'if' for real, possible situations. Alongside jestli, it is a very common everyday word for 'if' in real conditions, and is slightly more casual than jestliže or pokud.
- Když budeš mít čas, přijď. (If you have time, come over.)
Note: If the condition is in the future, Czech requires the future tense, not the present tense like English (Když budeš mít čas, not máš). For hypothetical or unreal conditions ('If I were rich'), use kdyby + kondicionál instead. Note that writing když bych is incorrect; you must use kdybych instead.
3. Grammar and Punctuation
A clause starting with když must always be separated by a comma. An important exception is the compound conjunction i když (even though), where the comma precedes the i (e.g., ..., i když...). Also, když does not push the verb to the end of the sentence. It simply takes the first position in its clause, forcing clitics into the second position (e.g., Když jsem se vzbudil...).
4. Causal 'Since' or 'Seeing as'
Když can also be used to express a reason, similar to 'since' or 'seeing as' in English.
- Když nemáš peníze, tak to nekupuj. (Since you don't have money, don't buy it.)
Examples (5)
- Když jsem byl malý, bydleli jsme na vesnici.
When I was little, we lived in a village.
Word by Word: When am-I was small, lived are-we on village.
Used for a past temporal state. Notice the clitic 'jsem' immediately following 'když'.
- Když prší, zůstávám doma.
When it rains, I stay home.
Word by Word: When rains, stay-I at-home.
Used for a habitual or repeated action in the present.
- Když budeš mít čas, zavolej mi.
If you have time, call me.
Word by Word: If will-you to-have time, call to-me.
Used as 'if' for a real condition. Note the use of the future tense (budeš mít) for a future condition, unlike English.
- Nevím, co budu dělat, když to nevyjde.
I don't know what I'll do if it doesn't work out.
Word by Word: Not-know-I, what will-I to-do, if it not-works-out.
A conditional 'if' in the middle of a sentence. The comma before 'když' is mandatory.
- Když se na to podíváš zblízka, uvidíš tu chybu.
If/When you look at it closely, you will see the mistake.
Word by Word: If/When yourself on it look closely, will-see-you that mistake.
Here, 'když' blends the meaning of 'when' and 'if'. The clitic 'se' takes the second position.
Common Mistakes
Using 'když' where 'až' stresses one future moment.
Different MeaningKdyž přijdu domů, zavolám ti.Až přijdu domů, zavolám ti.'Když přijdu domů, zavolám ti' is correct and very common. 'Až' is also correct and stresses one particular moment in the future. 'Když' also means 'if' and 'whenever', and it is used for past events.
Using the present tense for a future condition.
Different MeaningKdyž máš čas zítra, pomoz mi.Když budeš mít čas zítra, pomoz mi.'Když máš čas zítra, pomoz mi' is correct: Czech often uses the present tense for a time that is still ahead. 'Když budeš mít čas zítra' stresses that the time is in the future, but both are natural.
Using 'když' for indirect questions instead of 'kdy'.
Nevím, když to začne.Nevím, kdy to začne.Když is a conjunction, not a question word. For indirect questions ('I don't know when...'), you must use the interrogative adverb 'kdy'.
How It Connects
Learn This First
To use 'když' effectively, a learner needs to be comfortable with basic present tense verb conjugation and standard sentence structure. Since 'když' introduces both time and real conditions, familiarity with the temporal question word 'kdy' helps establish the logical connection for temporal usage.
- Basic SVO order
Knowledge of basic word order is essential for structuring complex sentences involving temporal or conditional clauses.
Level 1 - kde / kam / kdy / jakBasic Question Adverbs
The conjunction 'když' is functionally related to the temporal question adverb 'kdy', which provides the conceptual basis for temporal clauses.
Level 1
Related Patterns
- ažFuture Temporal Až
Contrasts with když; 'až' is used exclusively for single future events ('when I arrive tomorrow').
Level 3 - kde / kam / kdyRelative Adverbs of Place, Direction, And Time
'Kdy' is the question word 'when?', which learners often confuse with the conjunction 'když'.
Level 3 - kdyby + ConditionalHypothetical Kdyby Clause
'Kdyby' is used for unreal or hypothetical 'if' conditions, whereas 'když' is used for real, possible 'if' conditions.
Level 3 - Second-position clitics
'Když' occupies the first position in its clause, forcing clitics to immediately follow it.
Level 3 - jestli / zdaIndirect Yes-no Question
'Jestli' can also mean 'if' for real conditions, but unlike 'když', it can also mean 'whether' in indirect questions.
Level 3
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Practice když in Bubblegum
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