prey on
phrasal verbprey on/upon somebody/something
(of an animal or a bird )獸或鳥 to hunt and kill another animal for food 捕食;獵獲 Hawks prey on rodents and small birds. 鷹捕食齧齒動物和小鳥。
to harm somebody who is weaker than you, or make use of them in a dishonest way to get what you want 欺淩,坑騙,敲詐(弱者)