This is the 11768th most frequent Spanish word.
grises
"Grises" means "grays" in English.
In this sentence, 'grises' is used as an adjective to describe 'días,' implying the gray aspect of cloudy days.
Los días nublados suelen ser grises.
Cloudy days are often gray.
Here, 'grises' metaphorically indicates ambiguity or lack of clarity in the author's opinions.
Las opiniones del autor son bastante grises en su interpretación.
The author's opinions are quite gray in their interpretation.
'Grises' in this case describes the color of the cats, serving as an adjective for 'gatos.'