Always adapt to the noun you are referring to.
Leave is base form when saying something like the car is ____
Add an ending when describing a noun
The ____ car
The ending depends on whether the gender of the word itself
With ein words, gf the noun is neuter -> add an es. If masculine -> add an er. If feminine -> add and e
With der words, add an -e
Unpreceded adjective endings approximate the definite article that would be used:
- Add -e for feminine nouns.
- Add -er for masculine nouns.
- Add -es for neuter nouns.
- Add -en for plural nouns.