When a noun is the thing you want, order or buy, it changes its ending: masculine words drop their final -ς (ο καφές → τον καφέ), and ένας becomes έναν. Feminine and neuter words keep the same shape, but the "the" changes to την and το.
Examples
- Θέλω έναν καφέ, παρακαλώ.
- I'd like a coffee, please.
- Θέλω ένα νερό και μία σαλάτα.
- I'd like a water and a salad.
- Πληρώνω τον λογαριασμό.
- I'm paying the bill.
The mistake to avoid
Saying "Θέλω ένας καφές" — the subject form can't be used for what you're ordering.
Where this fits in
Food & ordering, Greek A1: Order at a café or restaurant, ask for the bill, and talk about basic food and drink.