trzeba + Infinitive

Trzeba with an Infinitive

Level 2

Trzeba + Infinitive (e.g., trzeba iść) means 'it is necessary to' or 'one must.' It is an impersonal way to say something needs to be done.

How It Works

1. Usage and Meaning
Trzeba is used to express that an action is required by logic, rules, or circumstances. It is often translated as 'one must,' 'we need to,' or 'it's necessary.' Because it doesn't point to a specific person, it often sounds softer and more polite than direct commands.

2. Tense Changes
In the present tense, trzeba is invariable. To use it in other tenses, you add the 3rd-person singular neuter form of być:

  • Present: Trzeba (It is necessary)
  • Past: Trzeba było (It was necessary)
  • Future: Trzeba będzie (It will be necessary)
  • Conditional: Trzeba by / Trzeba byłoby (It would be necessary)

3. Choosing the Right Aspect
When using an infinitive, you must choose the correct verb aspect:

  • Use a perfective infinitive for a single, specific task (e.g., Trzeba kupić chleb - One needs to buy bread).
  • Use an imperfective infinitive for habits, ongoing processes, or general rules (e.g., Trzeba pić dużo wody - One should drink a lot of water).

4. Adding a Subject or Object
If you want to specify who must do the action, the person goes into the dative case (e.g., Trzeba mi odpocząć - I need to rest). Additionally, trzeba can be followed by a noun in the genitive case to show that a specific thing is needed (e.g., Trzeba nam spokoju - We need peace).

5. Negation
When you say nie trzeba, it means 'it is not necessary' (you don't have to). It does not mean 'it is forbidden.' For prohibition, use nie wolno.

Examples (5)

  1. Trzeba kupić chleb.

    It is necessary to buy bread / We need to buy bread.

    Word by Word: Necessary to-buy bread.

    A general statement of necessity using the present tense.

  2. Trzeba było nam powiedzieć wcześniej.

    You should have told us earlier / It was necessary to tell us earlier.

    Word by Word: Necessary was to-us to-tell earlier.

    The past tense form 'trzeba było' combined with a dative pronoun 'nam' (to us).

  3. Żeby zdać egzamin, trzeba się uczyć.

    To pass the exam, one must study.

    Word by Word: In-order-to to-pass exam, necessary [reflexive] to-study.

    Expressing a logical requirement for a specific goal.

  4. Nie trzeba teraz dzwonić.

    It's not necessary to call now.

    Word by Word: Not necessary now to-call.

    Negation indicates a lack of obligation, not a prohibition.

  5. Trzeba będzie jutro wcześnie wstać.

    It will be necessary to get up early tomorrow.

    Word by Word: Necessary will-be tomorrow early to-get-up.

    The future tense construction using 'będzie'.

Common Mistakes

  • Using a nominative subject (like 'ja' or 'ty') with trzeba.

    Ja trzeba iść do domu.
    Muszę iść do domu. / Trzeba mi iść do domu.

    Trzeba is impersonal. You cannot use 'ja' (I). Use the conjugated verb 'muszę' or put the person in the dative case ('mi').

  • Using 'nie trzeba' to say something is forbidden.

    Different MeaningNie trzeba tu palić.
    Nie wolno tu palić.

    'Nie trzeba tu palić' is a good sentence, but it means 'there is no need to smoke here'. To say that smoking is forbidden, use 'nie wolno': 'Nie wolno tu palić.'

  • Following 'trzeba' with a conjugated verb.

    Trzeba idę do sklepu.
    Trzeba iść do sklepu.

    When a verb follows 'trzeba', it is an infinitive (the basic form ending in -ć or -c): 'trzeba iść'. A clause with 'żeby' is also possible, as in 'trzeba, żebyś poszedł'. A conjugated verb like 'idę' cannot follow 'trzeba' directly.

How It Connects

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trzeba + InfinitiveLevel 2Trzeba with an Infinitive

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Learn Modal Verbs With Infinitives before Trzeba With An Infinitive.

Words in This Pattern

trzeba