In this case, -α is feminine singular, as in μια γυnaika, μια καρεκλα (a woman, a chair) The feminine plural is -ες : δυο γυναικες, τρεις καρεκλες (two women, three chairs ) Thus, μια εφημεριδα, δυο εφημεριδες - one newspaper two newspapers
Hope that is clear enough. Please come back if it needs more explanation.
Apologies for no accents.
There are several endings for nouns and adjectives, which makes Greek more complicated than English. Take it a bit at a time and don’t get put off – it all becomes clear as you get more exposure to it all.
But to answer your question briefly: -α is feminine singular ( η υθναικα ) or neuter plural (τα βιβλια )
-ος is masculine singular ( ο σκυλος)
I won’t give more details than this at the moment in order to keep the answer more useful than confusing. Somewhere in this course, or on the internet you will find full tables of noun endings but these are usually very complex and off-putting. Take it σιγα σιγα (slowly slowly) and good luck.
Very simplified summary: -ος - masculine singular -οι masculine plural
-a (and also -η ) - feminine singular -ες feminine plural
-ο (and also -ι ) - neuter singular -α (and also -ια) - neuter plural
Hope that helps.
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