μέρα (mera) or ημέρα (imera).Both are correct.
I can speak Greek, This is how you say it: Σήμερα γιορτάζουν
μέρα [mera] < η-μέρα [ee-mera] see ephemera
σήμερα [seemera] = today
Kali Mera=Good day (GREEK)
Kali mera (Kah-lee- MARE-uh)
Its ημέρα (imera) Like the goddess Hemera.
"Τι όμορφη μέρα!" [ tee Omorfee mEra!]
You can say "You too!" in response to someone wishing you to have a good day.
HAVE A GOOD DAY ] IN APACHE LANGUAGE
S'agapo (Sah-ga-POH)
The Romanian language equivalent of good day is bună ziua.
Good day. That is what they say.
If in your question, "Singapore" is a language, then well, you still say Good Day. Otherwise, people greet with whatever language or way they are used to, be it "Hi", "Hello", and similar meanings in any language they prefer to greet in.
To say the word turtle in the Greek language you say chelona. In the Latin language this word is said as turtur.
uVa na siku rinene
Bicycle in Greek is "ฯฮฟฮดฮฎฮปฮฑฯฮฟ" (podรญlato).
telescopeo
Virginia in Greek is pronounced "ฮฮนฯฯฮถฮฏฮฝฮนฮฑ" (Virtzinia).
νίκη