Modal Verbs and the Infinitive

01

The Five Modals

• moct - can, to be able: můžu, můžeš, může
• muset - must, to have to: musím, musíš, musí
• chtít - to want: chci, chceš, chce
• smět - may, to be allowed: smím, smíš, smí
• mít - should, to be supposed to: mám, máš, má

• Můžeš mi pomoct?

  Can you help me?

• Máš tu počkat.

  You are supposed to wait here.

Moct also appears as mohu, mohou in careful writing beside the everyday můžu, můžou. Both are correct and you will meet each.

• Čím vám mohu pomoci?

  How can I help you?

02

The Trap in the Negative

Nemusím and nesmím are not two ways of saying the same thing, and the difference matters. Nemusím lifts an obligation: nothing compels you. Nesmím imposes a prohibition: you are forbidden.

• Nemusíš čekat.

  You don't have to wait.

• Nesmíš čekat.

  You mustn't wait.

03

Knowing How Is Not Being Able

Moct covers being in a position to do something. For a skill you have learned, Czech uses umět instead, and putting moct in its place sounds wrong to a Czech ear.

• Umí hrát na klavír.

  She can play the piano.

• Nemůžu dnes hrát.

  I can't play today.

04

Which Aspect After a Modal

Both aspects appear in the infinitive and keep their usual sense: the imperfective names an activity, the perfective a job to be got done.

• Musím uklízet.

  I have to do the cleaning.

• Musím uklidit kuchyň.

  I have to clean the kitchen.

05

Permission and Prohibition

Smět is about what the rules allow, where moct is about what circumstances allow. In practice smět is heard most in its negative, warning someone off, and it is the sharper of the two.

• Smím se zeptat?

  May I ask?

• Tady se nesmí kouřit.

  Smoking isn't allowed here.

06

The Infinitive on Its Own

An infinitive can also be the subject of a sentence. It counts as neuter, so any adjective describing it takes the neuter ending.

• Hrát tenis není snadné.

  Playing tennis isn't easy.

• Učit se jazyk je těžké.

  Learning a language is difficult.

07

Modals in the Past and Future

A modal forms its past and future like any other verb; the infinitive after it never changes. In the past the modal takes the participle and the auxiliary, and the second verb stays exactly as it was.

• Musel jsem pracovat.

  I had to work.

• Nemohla jsem přijít.

  I couldn't come.

• Budeš muset počkat.

  You will have to wait.

08

A Modal With No Second Verb

Where the action is obvious, the infinitive is simply dropped and the modal takes a direct object or an adverb of place on its own. English usually needs the second verb; Czech does not.

• Musím domů.

  I have to go home.

• Chci kávu.

  I want a coffee.

09

Motion Verbs Take One Too

After a verb of going, an infinitive states the errand, where English would use to or a gerund.

• Jdu nakupovat.

  I'm going shopping.

• Půjdu se podívat.

  I'll go and have a look.