Infinitive after evaluative adjectives

The pattern infinitiv po hodnotících adjektivech is used to evaluate, judge, or assess an action. It forms an impersonal clause where the agent is assumed to be general ('one' or 'people in general').

Structure and Syntax
The structure consists of the copula verb být in the 3rd-person singular (je, bylo, bude, by bylo) + a neuter singular evaluative adjective (ending in -é for hard adjectives, or -í for soft adjectives and comparatives like lepší, snazší) + an infinitive. Syntactically, the infinitive actually acts as the subject of the clause, while the adjective and copula form the nominal predicate. Common adjectives used in this pattern include možné / nemožné (possible / impossible), důležité (important), dobré (good), and nutné (necessary).

The Role of 'To'
Czech does not use dummy subjects like the English 'it'. In a sentence like Je těžké to pochopit (It is hard to understand it), the word to is the direct object of the verb pochopit. Avoid using to as a dummy subject, especially with verbs that require a different case (e.g., use Je těžké tomu uvěřit, not Je to těžké uvěřit, because uvěřit takes the dative).

Word Order Flexibility
Because the infinitive is syntactically the subject, it can easily be moved to the front of the sentence for emphasis or to establish the topic (e.g., Pochopit to je těžké. = To understand it is hard). While the Je + adjective + infinitive order is the neutral default, fronting the infinitive is very common.

Verbal Aspect
The choice of verbal aspect in the infinitive is crucial and changes the meaning. Use a perfective infinitive for a single, completed action (e.g., Je těžké to pochopit. = It is hard to understand it [in this instance]). Use an imperfective infinitive for a general, repeated, or ongoing action (e.g., Je těžké to chápat. = It is hard to understand it [generally/always]).

Negation and Clitic Placement
To negate the pattern, simply negate the copula verb (e.g., není těžké, nebylo nutné). Clitics typically cluster in the second position of the clause, often right after the copula verb or the entire predicate (e.g., Je mi to nepříjemné poslouchat. or Není těžké se to naučit.).

Specifying the Agent
Because the clause is impersonal, if you need to specify who the evaluation applies to, you can use a prepositional phrase, typically pro + accusative (e.g., Je pro mě těžké to pochopit. = It is hard for me to understand it). However, Czech also frequently uses the bare dative case for experiencers, especially with adjectives describing subjective feelings or states (e.g., Je mi nepříjemné to poslouchat. = It is uncomfortable for me to listen to it). Additionally, when evaluating someone's moral character or behavior, use od + genitive. Note that in these cases, native speakers overwhelmingly prefer a finite že clause over an infinitive (e.g., Je od tebe hezké, že mi pomáháš. = It is nice of you to help me).

Register and Forms
The neuter adjective form (je těžké, je nutné) is stylistically neutral and used across all registers. You must use the neuter adjective, not an adverb (e.g., Je těžce to pochopit is incorrect). You may encounter a competing pattern using the short -o ending (je nutno, je možno). For passive participles, the short form is actually the standard and preferred choice (e.g., je zakázáno = it is forbidden, je povoleno = it is allowed). However, using -o with standard evaluative adjectives (je těžko to udělat) is perceived as archaic or overly formal in modern everyday Czech, with the notable exception of the highly frequent fixed phrase těžko říct (hard to say). For regular adjectives, the neuter -é form is the dominant and fully standard choice.

Contrast with Reflexive Passives
Do not confuse this pattern with the impersonal reflexive construction with se. The reflexive pattern uses an adverb and promotes the patient to the nominative subject (Ta kniha se těžko čte. = That book reads with difficulty). The infinitive pattern uses a neuter adjective and keeps the patient in the accusative (Je těžké číst tu knihu. = It is hard to read that book).