niejest

Nie jest is the standard Polish negation construction used to negate a predicate in the present tense. It consists of the negation particle nie placed before the finite verb być (to be) in its present tense form, here jest. The expression translates roughly as “is not” or “isn’t” and is used to deny a state, identity, or property.

Grammatical notes: nie is always a separate word and is positioned directly before the verb. Polish does not contract nie with the following word. Nie jest can negate adjectives, predicative nouns, or entire clauses: for example, To nie jest prawda (That is not true), On nie jest lekarzem (He is not a doctor), Nie jest jasne, co się stało (It is not clear what happened). In questions, it can appear as Czy to nie jest prawda? (Isn’t that true?).

Usage and scope: The construction is common in both formal and informal Polish. It can negate present-tense predicates as well as predicates embedded in larger sentences, including subordinate clauses: Wiem, że to nie jest możliwe (I know that this is not possible). When referring to past states, the corresponding forms use past tense of by być: to nie była/p... nie było (that was not). The choice of tenses affects meaning but the basic negation pattern remains nie + jest or forms of być.

See also: Polish grammar, negation in Polish, быть (to be), predicative constructions.