短語 the leader of the pack 的意思是領頭者，起領頭作用。
Bradley Wiggins is the leader of the pack in the Tour de France!
For many, Madonna is seen at the leader of the pack in the world of female pop stars.
短語 a pack mentality 的意思是跟著集體走，缺乏獨立思考和計劃，一種從眾心態。
For example: The boys' pack mentality meant that they couldn't find their way out of the forest.