Mixed Endings of the Adjectives
We already know two sets of forms for adjective attributes:
definite article (or der-word) + adjective with weak ending + noun
(no article) + adjective with strong ending + noun
That leaves the adjectives preceded by the indefinite article ein. You will remember that the indefinite plural always requires an adjective with a strong ending, but what about the singular? Take a look at these forms:
| Masculine Singular (and Plural) | ||
| Nominative | ein guter Freund | gute Freunde |
| Genitive | eines guten Freundes | guter Freunde |
| Dative | einem guten Freund | guten Freunden |
| Accusative | einen guten Freund | gute Freunde |
|
Feminine - Singular (and Plural) |
||
| Nominative | eine gute Freundin | gute Freundninnen |
| Genitive | einer guten Freundin | guter Freundinnen |
| Dative | einer guten Freundin | guten Freundinnen |
| Accusative | eine gute Freundin | gute Freundninnen |
|
Neuter -Singular (and Plural) |
||
| Nominative | ein liebes Kind | liebe Kinder |
| Genitive | eines lieben Kindes | lieber Kinder |
| Dative | einem lieben Kind | lieben Kindern |
| Accusative | ein liebes Kind | liebe Kinder |
In the singular, after the indefinite article the adjective uses the weak endings in all cases in which the article clearly marks the case of the noun. That turns out to be all forms but three.
Remember, the masculine and neuter indefinite article in the nominative singular case is just ein. And this is also true for the neuter indefinite article in the accusative singular case. (ein Mann, ein Kind). This ein is just too unspecific for the German system. Therefore, you use the strong endings after ein.
Let's see how the adjective endings look when the adjective is preceded by the indefinite article. Here the strong forms are bold, the weak forms are not.
| Singular - Masc. | Singular - Fem. | Singular - Neuter | |
| nominative | -er | -e | -es |
| genitive | -en | -en | -en |
| dative | -en | -en | -en |
| accusative | -en | -e | -es |