This is the 12274th most frequent Portuguese word.
rápidas
"Rápidas" means "rapids" (fast-flowing sections of a river).
Here, 'rápidas' functions as an adjective describing the intensity or pace of the 'corridas' (races).
As rápidas corridas dos atletas impressionaram o público.
The fast races of the athletes impressed the audience.
In this context, 'rápidas' describes the speed of 'palavras' (words), suggesting promptness or urgency in communication.
Ele respondeu com rápidas palavras ao anúncio.
He replied with quick words to the announcement.
Here, 'rápidas' modifies 'mudanças' (changes), indicating their swift occurrence or abruptness.