インコ

How it works

は (topic) sets up the topic — “as for parakeets…” — then を (object) marks what gets acted on (言葉(ことば) (words)). The verb 真似する(まねする) (mimic) is a noun (真似(まね) (imitation)) glued to する (do), here left in plain present tense, which reads as a general truth: this is just what they do.