Questions & Answers about Πόσα βιβλία έχεις στο σαλόνι;
Πόσα means how many.
It comes from the adjective πόσος, -η, -ο (how much / how many). Like other Greek adjectives, it changes form to agree with the noun in:
- gender
- number
- case
Here the noun is βιβλία (books), which is:
- neuter
- plural
- accusative
So πόσος must take the neuter plural accusative form:
- masculine plural: πόσοι
- feminine plural: πόσες
- neuter plural: πόσα
Because βιβλία is neuter plural, we say Πόσα βιβλία = How many books.
The singular is βιβλίο (book), a neuter noun ending in -ο.
Most modern Greek neuter nouns ending in -ο form the plural with -α:
- το βιβλίο → τα βιβλία (the book → the books)
- το σπίτι → τα σπίτια (the house → the houses)
- το παιδί → τα παιδιά (the child → the children)
So βιβλίο becomes βιβλία in the plural. There is no form βιβλίοι in modern Greek.