Translation:Αυτός ο άντρας
No, you need the article before "άντρας". Greek even uses the article before proper names. "Η Μαρία και ο Γιώρος είναι εδώ." Maria and George are here.
Because άντρας is masculine and not neuter.
The word for „this“ has to agree in gender with the noun it describes.
Before a feminine word, you would have e.g. αυτή η καρέκλα for „this chair“.
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Can someone please tell me how I get the ending 'σ' or 's', on my keyboard, It tells me I have typos in my answer because of this but I don't know how to change it...
On my Android the final ς is found on the top left of the Greek keyboard...above the normal Σ. Hope that works for you. Or sometimes if you click on a letter and hold it for an extra second other options appear...accents etc. If these don't work get back to us and I'll ask someone who has a Galaxy.
See the comment below by Mizinamo. I think it's what you're looking for.