This is the 19th most frequent Greek word.
αλλά
"Αλλά" means "but" in English.
In this sentence, "αλλά" is employed to connect two ideas where the second presents an additional thought before proceeding with the first action.
Πρέπει να διαβάσεις, αλλά πρώτα ας φας κάτι.
You have to study, but let’s eat something first.
Here, "αλλά" is used to introduce an alternative option or preference to the idea presented earlier.
Δε θέλω να κανονίσουμε για αύριο, αλλά για την επόμενη εβδομάδα.
I don't want us to make plans for tomorrow, but for next week.
The word "αλλά" is used here as a conjunction to indicate contrast between the first clause (wanting to go to the beach) and the second clause (starting to rain).