German exercise: adjective endings (B2)

An adjective in front of a noun takes an ending that depends on three things: the gender of the noun, its case, and the word in front of it. After der, die, das and words like dieser and jeder, the article already shows gender and case, so the adjective takes a weak ending: -e in the nominative singular and in the accusative singular for feminine and neuter nouns, and -en everywhere else, as in "der alte Mann" and "dem kleinen Kind".

With no article, the adjective has to show gender and case itself and takes the ending der, die or das would have had: "guter Wein", "kaltes Wasser", "starken Kaffee". After ein, kein and possessives such as mein, the endings are weak except in the three places where ein has no ending of its own (masculine nominative, neuter nominative and accusative), where the adjective takes -er or -es: "ein interessantes Buch", "mein altes Auto".