-cí (dějový přívlastek)

Register and Usage
This form is extremely common in literature, journalism, academic texts, and official documents. However, it sounds stiff and unnatural in everyday casual speech. In spoken Czech, native speakers overwhelmingly default to a relative clause using který (saying muž, který tam stojí instead of tam stojící muž).

Reflexive Verbs
When forming participles from reflexive verbs, the reflexive pronoun (se or si) is retained and typically follows the participle as a separate word. Examples: smějící se chlapec (a laughing boy), blížící se vlak (an approaching train).

Word Order and Punctuation
When the active participle stands alone, it usually goes before the noun (e.g., hořící dům = a burning house). If it is expanded by an object or an adverbial phrase, the entire participial phrase typically stands after the noun it modifies (e.g., žena žehlící košili = a woman ironing a shirt). However, pre-positioning expanded phrases is also possible and quite common with short adverbs (e.g., anglicky mluvící zaměstnanec = an English-speaking employee), or in highly formal and bureaucratic texts even with objects (e.g., košili žehlící žena). When placed after the noun, punctuation depends on whether the phrase is essential to identify the noun: if it is essential (restrictive), there are no commas (e.g., Žena žehlící košili je moje matka.). If it adds extra, non-essential information (non-restrictive), it is set off by commas (e.g., Moje matka, žehlící košili, sledovala televizi.).

The Spelling Trap: Active vs. Purpose
A notorious spelling trap even for native speakers is confusing the active participle (long -ící) with adjectives of purpose (short -icí). This specific trap applies primarily to verbs ending in -it, but also to some others like péct (e.g., pečicí vs. pečící). For most other verb classes, including verbs ending in -et/-ět, the active participle and the purpose adjective are completely different words (e.g., uklízet forms the purpose adjective uklízecí but the active participle uklízející; psát forms psací vs. píšící; prát forms prací vs. peroucí).

• Active (dějové): Denotes an action currently happening. Uses the long vowel. Example: žena žehlící košili (a woman currently ironing a shirt).
• Purpose (účelové): Denotes what an object is designed for. Uses the short vowel. Example: žehlicí prkno (an ironing board).
• Abstract Nouns and Institutions: Systems, organizational bodies, and abstract concepts take the short suffix (purpose) because their function is general or timeless. Examples: řídicí orgán (governing body), hodnoticí komise (evaluation committee), řídicí systém (control system).

Note: A common myth taught in schools is that inanimate objects always take the short suffix. This is false! An inanimate object actively performing an action takes the long suffix (e.g., stroj čistící podlahu = a machine [currently] cleaning the floor, or přístroj měřící vlhkost = a device measuring humidity). Furthermore, designations of persons always take the long active suffix -ící because a person cannot be a 'tool of purpose' (e.g., řídící pracovník = a managing worker/manager).