Questions & Answers about Η πάγια εντολή λειτουργεί.
η is the definite article: the.
In this sentence, it is:
- feminine
- singular
- nominative
It matches εντολή, which is a feminine singular noun.
So η πάγια εντολή means the standing order / the permanent instruction, depending on the meaning already given to you.
Because the adjective has to agree with the noun it describes.
The noun εντολή is:
- feminine
- singular
- nominative
So the adjective also has to be feminine singular nominative:
- masculine: πάγιος
- feminine: πάγια
- neuter: πάγιο
That is why Greek uses πάγια εντολή, not πάγιος εντολή.