Accusative Adjective Agreement

The accusative case is primarily used for the direct object of an affirmative sentence. It is also triggered by certain prepositions showing motion, direction, or duration (e.g., przez, na, w). If the sentence is negative, a direct object switches to the genitive case. However, this negation rule only applies to direct objects of verbs—objects of prepositions stay in the accusative even in negative sentences (e.g., Nie czekam na dobrą kawę — I am not waiting for good coffee). When a noun takes this case, its adjectives must match.

Here are the endings for singular adjectives:

• Feminine: Simply change the nominative -a ending to -ą (e.g., dobra becomes dobrą, tania becomes tanią, polska becomes polską). Note that feminine accusative nouns usually end in -ę, so the adjective and noun do not perfectly rhyme! Additionally, some feminine nouns end in a consonant (e.g., noc, rzecz) and take no ending in the accusative, creating another scenario where they don't rhyme (e.g., nową rzecz — a new thing).
• Masculine Animate: Borrows the genitive ending -ego (e.g., dobrego). True soft-stem adjectives retain their i before the ending (e.g., taniego, ostatniego). This applies to people and animals, but also to many grammatically animate objects like fruits (banan), currencies (dolar), and some technology nouns in their animate-pattern uses; variants depend on the noun and register.
• Masculine Inanimate & Neuter: Stays exactly the same as the nominative form (e.g., dobry for masculine inanimate, dobre for neuter).

For plural adjectives:

• Masculine-Personal (Virile): Uses the same forms as genitive plural, -ych or -ich (e.g., Widzę dobrych studentów — I see good students). These forms are accusative here even though they match genitive.
• All other plurals (Non-virile): Takes -e or -ie (e.g., dobre). Note: While animals are masculine animate in the singular, they fall into this non-virile category in the plural (e.g., dobre psy — good dogs, not dobrych psów in an affirmative accusative phrase).

Spelling Rule: If the adjective stem ends in k or g, use the softer vowel variants to preserve the sound. This applies to the singular (e.g., długi becomes długiego, not długego) as well as the plural forms, which take the i variants (e.g., długie instead of długe, and długich instead of długych).

Note on "this" (ten) and possessives: Traditional grammar books insist that the feminine accusative form of "this" is tę (e.g., Widzę tę kobietę — I see this woman). However, in everyday spoken Polish, native speakers very commonly use tą. While tę is required for formal writing, tą is completely natural in casual speech. In contrast, possessive pronouns (like mój, twój, nasz) behave exactly like standard adjectives and in the feminine accusative take the regular -ą ending (e.g., moją, twoją, naszą).

Other possessive forms follow the same case agreement: Widzę mojego brata (I see my brother), Mam twój telefon (I have your phone), Widzę naszych sąsiadów (I see our neighbors), Czytam twoje książki (I am reading your books). Invariant jego, jej, ich do not take these endings.