Adjectives After Possessives and Demonstratives

Learners often master the three adjective declensions — weak, mixed, strong — and then freeze the moment a real sentence forces a choice. The freeze is unnecessary. Once an adjective stands after a determiner, you do not have to reason about gender, case, and "which pattern" all at once. You ask a single question: what FAMILY does the determiner belong to? That one fact selects the pattern. A der-word triggers weak endings; an ein-word triggers mixed endings; nothing at all triggers strong endings. This page turns that daunting three-way choice into a lookup, and explains why the two families you meet most — demonstratives like dieser and possessives like mein — behave so differently even though they feel similar.

The single decision: which family?

Every German determiner falls into one of two declension families, plus the "no determiner" case:

• der-words decline like the definite article der/die/das. They always show the gender and case loudly. Members: dieser (this), jener (that), jeder (each/every), mancher (many a), solcher (such), welcher (which), and alle/beide (all/both) in the plural.
• ein-words decline like the indefinite article ein. Members: ein, kein, and all the possessives mein, dein, sein, ihr, unser, euer, Ihr.
• no determiner — the noun stands bare.

That classification is the whole game. Here is the lookup table:

Why the two families behave differently

The logic is the same one that ties all three declensions together: the gender and case must be marked exactly once in the noun phrase, and the strongest available signal carries it.

A der-word never lets you down. Dieser, diesem, diesen, dieses — every form carries a distinctive ending that pins down gender and case. Since the determiner has already done the marking, the adjective is free to relax into the colorless weak endings, just -e or -en.

An ein-word is defective. In three slots — nominative masculine (ein/mein), nominative neuter and accusative neuter (ein/mein) — it takes no ending at all and tells you nothing. In those three gaps the adjective must step up and carry a strong ending. Everywhere else the ein-word does inflect (einen, einem, meiner, meines…), so the adjective relaxes back to weak -en. That blend of strong-in-the-gaps and weak-elsewhere is exactly what "mixed" means.

So dieser and mein feel like twins — both come before a noun, both mean roughly "this/my" — but grammatically they are opposites. Dieser always speaks, so the adjective stays quiet (weak). Mein sometimes falls silent, so the adjective sometimes has to speak (mixed).

Demonstratives (der-words) → weak endings

After dieser, jener, jeder, welcher, mancher, solcher — and the plural quantifiers alle, beide — the adjective is weak in every cell. Here is the full paradigm with dieser:

Notice there are only two endings in the whole table: -e in the five "easy" cells (the nominative singulars and the feminine/neuter accusatives) and -en everywhere else. That is the weak declension in its entirety.

Possessives (ein-words) → mixed endings

After the possessives mein, dein, sein, ihr, unser, euer, Ihr — and after kein — the adjective follows the mixed pattern: strong in the three gaps where the ein-word shows nothing, weak everywhere else. Here is the paradigm with mein:

The three bold strong endings — mein guter Freund (-er), mein kleines Kind (-es, nom.), mein kleines Kind (-es, acc.) — are precisely the slots where mein is endingless. Compare them with the der-word table above: where dieser gave dieser gute Mann (weak -e), mein gives mein guter Freund (strong -er). That single difference — -e vs -er in the nominative masculine — is the clearest fingerprint of the two families.

No determiner → strong endings

When no determiner appears at all — common with mass nouns, plurals, and after numbers — the adjective alone must mark gender and case, so it takes the strong endings (the ones that mirror der/die/das itself).

For the full strong paradigm, see strong endings; the same no-determiner logic also governs adjectives after numbers, covered on the numbers-as-triggers page.

English contrast

English adjectives never change shape: "this good man," "my good friend," "good wine" — good is frozen in all three. So English gives you no instinct for the fact that dieser and mein should pull the adjective in opposite directions. The mental shift required is this: in German the determiner and the adjective form a team that together mark gender and case exactly once. A der-word is a strong teammate who does the marking, so the adjective coasts (weak). An ein-word is a teammate who sometimes goes missing, so the adjective covers for it (mixed). English has no such teamwork because nothing in an English noun phrase is marked for case in the first place.

Common Mistakes

The classic family mix-up: applying the mein-pattern after dieser. Because dieser already shows nominative masculine, the adjective must relax to weak -e.

The mirror error: applying the dieser-pattern after mein. Since mein shows nothing in the nominative masculine, the adjective must carry the strong -er.

Forgetting that even "easy" der-word phrases need an ending. In the dative the weak ending is -en; the adjective is never left bare.

The neuter gap. Mein before a neuter noun is endingless, so the adjective supplies the -es that das would otherwise have shown.

Key Takeaways

• One question decides everything: is the determiner a der-word, an ein-word, or none?
• der-words (dieser, jener, jeder, welcher, mancher, solcher, alle, beide) → weak endings (-e / -en).
• ein-words (ein, kein, and the possessives mein, dein, sein, ihr, unser, euer, Ihr) → mixed endings.
• No determiner → strong endings.
• The reason: der-words always mark gender/case, so the adjective coasts; ein-words fall silent in three slots, so the adjective covers for them there.
• The fingerprint of the difference is the nominative masculine: dieser gute Mann (weak) vs mein guter Freund (strong).