-no / -to

The -no/-to construction is a unique feature of Polish grammar. It functions as an impersonal past tense, meaning the 'who' of the sentence is left unspecified, though it is always understood to be a human being. The verb form is completely frozen and invariable, never changing for gender or number. Because the endings look like neuter passive participles, beginners frequently try to make the verb agree with the object's gender (e.g., *otwarta wystawę) – do not do this! Furthermore, this construction is strictly for the past tense. For present or future impersonal actions, you can use the impersonal się construction (e.g., buduje się, będzie się budować) or the third-person plural (e.g., zbudują). Note that while -no/-to is exclusively past tense, the się construction can be used across all tenses.

1. Formation
These endings are attached to the past or infinitive stem using the exact same phonetic rules as passive participles. However, this pattern is applied to many verbs, even intransitive ones that lack a passive participle (though there are common exceptions that lack this form entirely, such as być and iść):

• -no: Used where a passive participle would end in -ny. Examples: czytać → czytano (one read); spać → spano (one slept).
• -ono: Compare robić → robiono (people did), uczyć → uczono (people taught), and piec → pieczono (people baked). The stem may alternate, so do not just remove -ć and add -no. This is a common -no subtype, not an ending for every verb in -ić/-yć/-c.
• -to: Used where a passive participle would end in -ty. Examples: bić → bito (one beat/hit); myć → myto (one washed).

2. Reflexive Verbs
If the verb is reflexive, the pronoun się is simply retained. Example: bawić się → bawiono się (one had fun).

3. The Role of Aspect
Just like the standard past tense, this construction respects verb aspect:

• Imperfective (e.g., budowano): Describes ongoing, repeated, or habitual actions in the past.
• Perfective (e.g., zbudowano): Describes completed, single events.

4. Syntax and Case Restrictions
There are two critical syntactic rules for this construction:

• Object Case: Unlike the passive voice, the object does not become the subject. The verb retains its normal case government (often the accusative, but it could be dative, instrumental, etc.).
• No Agent: The agent must remain completely anonymous. You cannot use the preposition przez to name the person who did the action. If you want to mention the agent, you must use a standard active or passive sentence.

5. Usage and Register
This pattern is especially common in standard written Polish, though it also occurs in everyday speech. You will encounter it in police reports, historical accounts, and journalism. In casual conversation, Poles prefer using the masculine-personal plural past ('mówili') or the impersonal się ('mówiło się').