这位年轻运动员成为了健康生活方式的代言人。

The young athlete became the ___poster-boy for a healthy lifestyle.

他整天沉迷游戏，有着反社交的习惯，简直是沙发土豆的代言人。

With his constant gaming and antisocial habits, he's the ___poster-boy for couch potatoes.