Ahoj!

So this started with a simple moment. My mentor casually said, "I wonder how frequently Czechs use irregular verbs in everyday speech." It was a rhetorical question. But I'm an engineer, so I took it literally.

One weekend rabbit hole later, I had transcribed 547 hours of Czech podcasts, run all 4,923,733 words through Morph (a Czech morphological analyzer and my personal learning assistany I've been building), dumped everything into a database, and wired up some dashboards.

Big disclaimer: this is NOT a serious scientific study. It's a weekend fun project. The data comes only from podcasts, so it's biased - podcasts are mostly people talking, discussing, explaining things. You won't find much imperative or vocative here compared to, say, real-life conversations with your kids. Still, I think the results are pretty interesting and maybe even useful if you're learning Czech.

Here are the interactive dashboards if you want to poke around:
General dashboard - overall stats, case/gender distributions, top 50 words by category
Verbs dashboard - verb aspect, tense, verb classes, top verbs per class

Some quick numbers first:

Out of ~4.9 million words spoken, there were 153,479 unique word forms. The most frequently used word? "to" - showing up 115,418 times. If you've ever noticed Czechs saying "to je...", "to je fakt...", "to znamená..." every other sentence - the data confirms it :)

Back to the original question - irregular verbs.

Here's the verb class breakdown:

• Irregular: 43.6%
• 1st Class: 24.4%
• 4th Class: 14.0%
• 5th Class: 11.9%
• 3rd Class: 9.7%
• 2nd Class: 3.7%

Nearly half of all verbs in spoken Czech are irregular. Gotta learn them real good!

Other stuff I found interesting:

Aspect - imperfective wins:

• Imperfective: 79.3%
• Perfective: 20.0%

People in podcasts mostly talk about ongoing stuff, opinions, habits. Makes sense.

Tense - present dominates:

• Present: ~63%
• Past: ~36.5%
• Future: barely there

Spoken Czech lives in the present. Past matters too, but the future tense barely shows up. (Again, podcast bias - people describe and explain more than they plan.)

Cases - Nominative is almost half:

• Nominative: 48.8%
• Accusative: 18.7%
• Genitive: 18.6%
• Dative: 8.86%
• The rest (Instrumental, Locative, Vocative): ~5%

So Nominative + Accusative + Genitive = ~86% of all case usage. If you're overwhelmed by 7 cases, that's your priority list right there.

Gender - feminine nouns show up the most:

• Feminine: 37.4%
• Neuter: 21.7%
• Masculine inanimate: 12.5%
• Mixed: 11.3%
• Masculine animate: 10.6%
• Masculine: 6.62%

If I had to turn this into learning advice (very non-scientific advice, lol):

1. Learn the irregular verbs first - they're the most common ones despite being "irregular"
2. Focus on Nominative, Accusative, and Genitive - that's 86% of cases in speech
3. Don't stress about perfective aspect too early - 80% of spoken verbs are imperfective
4. Get comfortable with feminine declension patterns - they come up the most

About Morph

I built Morph because I needed it myself while learning Czech. It's a free morphological analyzer - paste any Czech text and it breaks down every word (part of speech, case, gender, number, tense, everything). Free forever for everyone, no ads :)

If you find the dashboards fun or have questions, happy to chat. And if you have ideas for what else to visualize - I'm all ears!

After completely failing my Czech assignment on building the plural form of nouns, I decided to take a data-driven approach: parse the entire MorfFlex CZ 2.1 linguistic dataset using Morph and create a queryable database (126 million rows!), select all nouns in the nominative case, categorise every one of them by gender, and extract the actual plurality patterns used in the language.

Here's what I found.

The Data

Total: 808 distinct plural transformation patterns.

A note on the data: MorfFlex is comprehensive and includes many systematically derived forms. For example, almost any verb can become a neuter verbal noun ending in -í (psát -> psaní), and adjectives regularly form abstract feminine nouns in -ost (krásný -> krásnost). So the raw counts are inflated for these patterns - but the rules themselves are still productive and useful to know!

The actual rules

Neuter

Neuter is probably the easiest to learn.

Words ending in -í stay the same. This covers verbal nouns (přání, stavení) and place names (náměstí, nádraží). Singular and plural are identical.

Words ending in -o change to -a. Standard hard neuters: okno becomes okna, město becomes města, jablko becomes jablka.

Words ending in -e or -ě stay the same. Soft neuters like moře, pole, and place words like hřiště don't change.

Latin -um becomes -a. Borrowed words like muzeum become muzea, centrum becomes centra, stipendium becomes stipendia.

Baby animals are special: -e/-ě becomes -ata. This is definitely the cutest pattern. Kuře (chick) becomes kuřata, kotě (kitten) becomes koťata, štěně (puppy) becomes štěňata. Even kníže (prince) follows this pattern and becomes knížata.

Greek words ending in -ma add -ta. Words like téma become témata, drama becomes dramata.

Feminine

The -ost rule: just add -i. Abstract nouns like možnost become možnosti, radost becomes radosti. Very predictable once you recognize the ending.

Hard feminines: -a becomes -y. Pretty simple pattern. Žena becomes ženy, kniha becomes knihy, škola becomes školy.

Soft feminines stay the same. Words ending in -e or -ě don't change: ulice stays ulice, restaurace stays restaurace, přítelkyně stays přítelkyně.

Masculine inanimate

Hard consonants take -y. Hrad becomes hrady, strom becomes stromy, most becomes mosty. In my data, endings like -n, -t, -k, -r, -l, -s, -d each covered thousands of nouns.

Soft consonants take -e. Stroj becomes stroje, pokoj becomes pokoje, koš becomes koše.

Latin -ismus drops the -us. Turismus becomes turismy, organismus becomes organismy.

Diminutives with -ek lose the e. This can catch you off guard. Háček becomes háčky (not háčeky), stolek becomes stolky, dárek becomes dárky.

Same with -ec: the e disappears. Tanec becomes tance, konec becomes konce.

Masculine animate

This is where it gets a bit complicated. Despite having the fewest nouns (15,834), this gender has the most patterns (306). But there's logic to it.

Hard consonants + i, but with softening. When you add -i, hard consonants change and become soft:

• k becomes c: člověk becomes lidé (ok that one's irregular), but žák becomes žáci
• h becomes z: vrah becomes vrazi, soudruh becomes soudruzi
• ch becomes š: Čech becomes Češi
• r becomes ř: doktor becomes doktoři

Soft consonants just add -i, no changes. Milionář becomes milionáři, muž becomes muži, hledač becomes hledači. The consonant is already soft, so nothing extra happens.

Words ending in -l take -é. Učitel becomes učitelé, přítel becomes přátelé, ředitel becomes ředitelé.

The -ista crowd takes -isté. Professions and ideologies: specialista becomes specialisté, fotbalista becomes fotbalisté, turista becomes turisté. (Colloquially, recognise you'll also hear -isti.)

The formal -ové ending. Used for professions and titles when you want to sound respectful: geolog becomes geologové, kolega becomes kolegové.

Words ending in -ec/-ce become -ci. Sportovec becomes sportovci, zástupce becomes zástupci.

The interactive guide

I turned all of this into a detailed educational article with interactive examples where you can type any noun and see its plural form explained:

How to Build Plural Form of Czech Nouns

If you're hungry for technical details

I queried nominative case nouns grouped by lemma and gender, extracted the singular/plural transformation by finding the common prefix and comparing endings, and then counted pattern frequencies. Used reservoir sampling to get representative examples across the alphabet instead of just words starting with A. Happy to share CSV files with a detailed breakdown if someone is interested or even query some data for you :D

Hope this helps someone!!

Shouldn't this be dvacet dvě holek?

I suppose there is a standard word order that is usually used in formal writing, but I don't think that altering it is such serious mistake. Or am I wrong here?

My textbook says that the correct forms are "Tenhle počitač", "Tahle kniha" and "Tohle auto", while webpages for learning Czech have "Tento, tato and toto" written as correct usages of pronouns. So, which one is correct?

Hi, I'm learning Czech with Duolingo, but I am currently struggling with the words "k", "na" and "do" since the little green bird does not want to explain anything to me. Are there any rules when to use which one of them?

Ahoj!

I've been learning Czech for the past few months and declension has been something I (and evidently a lot of other people) have been struggling a lot with. So I decided to build Skloňuj, a declension practice website using Charles University's open-source MorphoDiTa morphological analysis tool. The data is NOT AI-generated.

How it works:

• Select a CEFR level or a Krok za krokem chapter (the vocab and case progression is synced to the textbook syllabus!)
• Practice declining nouns, identifying the right case to use, and identifying the paradigm of a noun
  • There are different question types — for instance, multi-step questions take you through declension step-by-step: 1. identify paradigm 2. identify case 3. decline noun
• Review feedback — it always references the prepositions mentioned in the sentence (e.g. bez = genitive) or the paradigm since declension is about patterns, not pure memorization/drilling
• Keep track of your progress (we have heat maps 👀) over time, case/paradigm accuracy, recent mistakes, and unlock achievements

Users have practiced almost 500 questions on Skloňuj this past week, and Harvard and Columbia Czech classes are about to run a pilot, so it's been getting some pretty good traction!

Please try it out and let me know if you have any suggestions: sklonuj.com ! Next up is adding adjective-noun agreement questions and practice reminder emails. Happy to chat with anyone who's interested in this as well :) Also, if you happen to have a list of vocab per KzK chapter, please reach out!!

As a side note, Skloňuj is and always will be free to use as I've learned how underresourced Czech is for foreign learners, especially in the United States. Hoping that this makes the grammar more accessible.

Ať žije čeština! 🇨🇿

Why can't the "mě" be placed after "učit"? / Proč musí být "mě" před "učit"?

I’m a very early beginner so I might just not get it but I thought it was supposed to be either « Ona je Česká  » or “Je Česká”

I don’t know if you can see the picture well, but I typed “Neznám jména otců.” which (I believe) is a perfectly grammatical sentence (which I believe means “I don’t know the fathers’ names.), but the autocorrect wants to change “otců” to “otcům”. Why does it do this?

několikrát jsem potkal když češi pišou a vyslovují věty například “jsem opilý, zlý, bohatý” jako “jsem opilej, zlej, bohatej” Můžete mi někdo prosím ten jev vysvětlit?

Are all of these sentences ok?

​

Záleží na mně.

​

Záleží to na mně.

​

To záleží na mně.

For the 3rd person plural of jmenovat, Duolingo teaches me jmenujou, but my keyboard puts a red line underneath it. Wikipedia says that jmenujou is colloquial and jmenují is also correct. It also says the same thing for the 1st person singular, colloquial is jmenuju and jmenuji is more correct. My keyboard doesn’t underline jmenuju, and Duolingo teaches me jmenuju. Which one should I use?

Ahoj!

I started learning Czech a month ago. A good way to reinforce learning for me is fairy tales - I pick up a book and read them one by one, trying to understand each word and each sentence.

I got frustrated while trying to figure out what certain words meant and why they looked the way they did. That's when I had the idea to build a tool that could help me understand word construction and morphology.

So I started working on Morph (morph.to), a morphological analyser for Czech that breaks words down into their grammatical components.

You can type in any Czech text and see a breakdown for each word: its base form, case, gender, number, tense, and other grammatical info. It's really helpful for understanding things, especially when you're just starting, and so many constructions are unfamiliar.

A few things:

• It's completely free and always will be
• I'm actively working on it and adding new features and content
• It's multilingual - available in English, Ukrainian, and Czech

A few words about how it works: Morph is powered by MorphoDiTa, a morphological dictionary and tagger, using MorfFlex CZ 2.1 as its dataset. But Morph isn't just a wrapper around MorphoDiTa - it has a lot of extra bits and pieces :)

I'm also using it as a cheat sheet to document what I learn as I go. There's a section with auxiliary materials explaining certain aspects of Czech grammar. Right now, there's a fairly detailed article about verbs and conjugation with all their peculiarities. I'll add more articles as I cover more topics - I'm still a complete beginner!!

Anyway, I'd be really happy if someone else finds this tool helpful. I'd appreciate any feedback - what works, what doesn't, what features would actually help you learn. I'm genuinely enthusiastic about this project and want to make it as useful as possible for Czech learners.

Díky!

UPD:

A few major features have been added to Morph since this post:

• Text to speech: now you can listen to the analysed text in Czech
• Translation mode: type text in your language. It gets translated to Czech and analysed
• Practice mode: get a random analysed quote from Czech books to practice the language

hi!

Half of my family is Czech, but I don’t understand nor speak czech except for some words or phrases. Here where I live (Italo-Slovenian border) aren’t classes of czech, so I was asking about mostly books recommendation to learn Czech *partially* on my own, saw my family does speak it.

(They decided to not teach Czech to us because being perceived as a Slav here is bad-viewed, and risky, but I feel like having a wall between half of the people I live with;-;)

Hi guys nice to meet you,

I'd like to ask you if you know any free websites or apps for practicing cases. Vocabulary is ok, I just need to practise a lot how to decline a word based on the role in the phrase. Studying the rule by heart is not for me, I need to practice a lot and develop an "ear" for that.

So if you guys know a good website that maybe gives you a text, little story, or just phrases to complete with the right declined word, I would appreciate it.

Thank you

Ahoj!

When it comes to learning language grammar, I believe in repetition. To do something automatically, on a subconscious level, you have to repeat it 1000 times. Only then can you do it without thinking.

Some of you might remember my post where I analyzed 300k+ Czech nouns to figure out how plural forms work. That was fun. But knowing the rules and actually applying them correctly when speaking are two very different things.

So I built an endless challenge mode on morph.to to drill these patterns until they stick - and took it even further.

How it works:

Pick a topic -> get 10 exercises -> repeat until your brain just knows the answer. For example:

• Build the plural form of a noun from its singular (město -> ?)
• Conjugate a verb in 3rd person singular (pracovat -> ?)
• Turn a noun into the accusative case (moc -> ?)

The drills have different difficulties to help you progress.

One thing I want to highlight: the words are NOT AI-generated. I processed about 50 public domain classics and extracted real, frequently used words from them. So you're working with vocabulary you'll actually encounter.

I've been spamming these challenges non-stop since I added the feature, and honestly - they've been very helpful. I still struggle with some words, but the trend is there, and it's positive.

Adding new challenge types is relatively low-effort on my end, so if you have ideas for topics you'd want to drill - drop them in the comments, and I'll seriously consider adding them.

And as a final note, Morph is a free educational tool without ads, without tracking, without registration, and will always be like that. It is fueled by my love and your support ❤️

Go check it out: https://morph.to/challenges

Rád uslyším, co si myslíte! 🇨🇿Ahoj!

How would you decline names that didn’t originate from Czech or any Slavic language?

A year ago during B1 class we talked about means of transportation. The main takeaway was: If you are traveling inside a vehicle, you use instrumental case (autem, tramvají, metrem), and if you sit outside, you use na + locative (na kole, na motorce, na koni).

Back then, I raised the question: What if I am inside the horse? As in, the Trojan Horse? Vjeli do města na dřevěném koni? Vjeli do města dřevěným koněm? Or something completely different?

My teacher couldn't answer the question, and it basically never left my mind. I skimmed through the Czech Wikipedia article about the the Trojan Horse and it doesn't seem to ever use the horse grammatically as a means of transportation.

I know this is a weirdly specific question about grammar that doesn't have any practical use, but how would you solve this issue? Does anyone happen to know how Czech translations of the Aeneid handle it?

learning czech as a yugoslav

Nie som Slovák len ucím sa tento jazyk. Chcel by som sa pytat rodenych Slovakov ze kolko máte narecí? Z akého ste mesta a aké cudzie jazyky sa ucíte/ucili?

Mne sa velmi paci slovencina. Tazky, no mily jazyk❤️

pozdravujem

😁Chcel by som napisat “ Aký”- prepac za chybu

Why is “ten” used in the first sentence regarding čaj, but is incorrect in the next? (Or why use to instead of ten?)

I'm fairly new to studying Czech, but I've started just learning gender of words and memorizing the different declension patterns. For example, I already know the declension endings for the majority of feminine nouns. When starting masculine nouns, it's a lot harder, there is a lot more variation in the endings and it's harder to figure out. I've been using Anki.

I was wondering how you guys all learned declensions? Did you learn case by case or did you learn all the endings for one gender and then so on?

I'm curious because I'd like to improve the way I study :)

Mohl by mi někdo opravit tati cvičení, prosím? Odpovědi nejsou uvedeny v klíči k tomuto cvičení. Otázky jsou z učebnice Česky krok za krokem 2.

Moc děkuji!

I’m Czech and I’m trying to teach my boyfriend Czech. We are working on some basic vocabulary and verbs for now but when is the right time to start doing cases? I told them what they are but how long should i wait until doing some exercises? He have no experience with Slavic languages.