Meaning: In this sentence, a particular cat was not moving and was attentively looking at a bird.
Choice of Words: Using "The" as an article to refer to a specific cat. "Sat" is a verb that means to be in a position with your body resting on a surface. "Still" is an adverb that means without moving. "Watching" is a verb that means to look at someone or something carefully or attentively. "Bird" is a noun that refers to a warm-blooded vertebrate animal with feathers, wings, and a beak.