This is the 253rd most frequent Greek word.
μεγάλες
"Big" or "large" (feminine plural).
Here, "μεγάλες" modifies "ελπίδες" (hopes), conveying a sense of seriousness or expectation.
Έχουμε μεγάλες ελπίδες για το μέλλον.
We have high hopes for the future.
In this example, "μεγάλες" qualifies "πόλεις" (cities), describing their size or extent.
Οι μεγάλες πόλεις είναι γεμάτες ζωή.
Big cities are full of life.
In this sentence, "μεγάλες" is an adjective describing the noun "αλλαγές" (changes), indicating largeness or significance.