In English, the main indefinite pronoun is one.
- “Do you want a coffee?”
“Yeah, I want one.”
One is the stand-in for “a coffee”.
The core function of indefinite pronouns is the same in German (and any language), but they’re a fair bit more complicated because they get “dressed up” for gender and case.
- “Willst du einen Kaffee?”
“Ja, ich will einen.”
- “Willst du ein Bier?”
“Ja, ich will eins.”
They’re based off of the indefinite articles ein-, but the endings vary a little bit.
Here they are, I highlighted the differences to the article table in green.
| nominative | Accusative | Dative | Genitive | |
|---|---|---|---|---|
| masculine | ein-er | einen | einem | eines (not used) |
| neuter | ein-s | ein-s | einem | eines(not used) |
| feminine | eine | eine | einer | einer (not used) |
| plural | welche | welchen | welchen | welcher (not used) |