Adjective endings after quantifiers (viele, alle, beide, einige, manche)

Ich kenne viele nette Leute, aber alle neuen Kollegen sind noch fremd.I know many nice people, but all the new colleagues are still strangers.

After a plural quantifier — viele, alle, einige, beide and the like — a following adjective takes one of two endings. After viele, einige, wenige, mehrere, andere it repeats the strong plural ending (viele nette); after alle, beide, sämtliche, manche, solche it's weak -en throughout the plural (alle neuen). The whole topic is knowing which group a word belongs to.

Quick shortcut: after viele, einige, wenige, mehrere, andere the adjective repeats the same strong plural endings the quantifier itself shows — -e (nom./acc.), -en (dative), -er (genitive). After alle, beide, sämtliche, manche, solche — and after a plural possessive like meine or keine — the adjective is weak -en right through the plural.

Group 1: the quantifier and the adjective run in parallel

viele, einige, wenige, mehrere, andere, etliche, verschiedene — these behave like adjectives themselves. They take strong plural endings, and the adjective after them simply repeats the same ending:

• Viele junge Menschen ziehen in die Stadt. (Many young people move to the city.) — nominative → -e / -e
• Ich habe einige gute Bücher gelesen. (I read some good books.) — accusative → -e / -e
• Sie arbeitet mit mehreren neuen Kollegen. (She works with several new colleagues.) — dative → -en / -en
• Das ist die Meinung vieler erfahrener Lehrer. (That's the opinion of many experienced teachers.) — genitive → -er / -er

ein paar ("a few") belongs here in spirit but never changes its own form: ein paar gute Ideen, mit ein paar guten Ideen — the adjective still takes the full strong ending.

Group 2: the quantifier acts like a der-word

alle, beide, sämtliche, solche, manche carry the der-word plural endings themselves, so the adjective drops to weak -en in every plural case. Plural possessives (meine, deine, keine …) work the same way — meine guten Freunde, mit meinen guten Freunden. (In the singular, a possessive is an ein-word and follows the mixed pattern instead.)

• Alle neuen Studenten sind willkommen. (All new students are welcome.) — nominative → -en
• Ich kenne beide kleinen Kinder. (I know both little children.) — accusative → -en
• Mit allen guten Wünschen. (With all good wishes.) — dative → -en
• trotz sämtlicher bekannten Probleme (despite all the known problems) — genitive → -en

With beide and manche you'll also see the strong plural ending (beide kleine Kinder, manche gute Leute); both are accepted, but the weak -en is the more common choice and the one to lean on.

The singular der-words: mancher, solcher, welcher

In the singular, mancher, solcher and welcher are full der-words — they inflect exactly like dieser, and the adjective after them is weak:

• mancher alte Freund (many an old friend) — nominative masculine
• bei solchem schlechten Wetter (in such bad weather) — dative neuter
• welches interessante Buch? (which interesting book?) — nominative neuter

Two of them have an uninflected form used right before ein: manch ein guter Freund, solch ein schöner Tag — here manch / solch carry no ending, so the adjective simply follows the normal mixed declension after ein.

Common mistakes

• ❌ viele guten Freunde → ✅ viele gute Freunde (after viele the adjective is strong in the nominative/accusative — -e, not -en)
• ❌ alle nette Leute → ✅ alle netten Leute (after alle the adjective is always weak — -en)
• ❌ mit viele neue Ideen → ✅ mit vielen neuen Ideen (dative plural: both words take -en)
• ❌ bei solchem kalte Wetter → ✅ bei solchem kalten Wetter (singular solcher is a der-word — the adjective is weak -en in the dative)
• ❌ einige interessante Bücher is correct — but ❌ einige interessanten Bücher is the typical overcorrection to avoid

Quick check

Fill in the correct endings.

1. Viel___ alt___ Häuser wurden renoviert. (nominative plural, after viele)
2. Ich habe mit einig___ nett___ Nachbarn gesprochen. (dative plural, after einige)
3. All___ neu___ Mitarbeiter bekommen einen Ausweis. (nominative plural, after alle)
4. Bei solch___ kalt___ Wetter bleibe ich zu Hause. (dative neuter singular, after solchem)

Key takeaways

• German quantifiers fall into two groups, and the group decides the adjective ending.
• Group 1 (viele, einige, wenige, mehrere, andere): the adjective repeats the strong plural endings -e / -e / -en / -er.
• Group 2 (alle, beide, sämtliche, manche, solche, and plural possessives): the adjective is weak -en throughout the plural.
• In the singular, mancher, solcher, welcher are der-words — the adjective after them is weak, which in the nominative means -e, not -en (mancher alte Freund).
• ein paar never inflects; manch and solch directly before ein stay uninflected, and the adjective then follows the normal ein-word pattern.