Hi! Theses days, I've really enjoyed watching american TV show "Modern Family". I think the show is really good, sometimes fun and helpful for foreigners to learn casual English. Yesterday I watched episode 2 in season 1. The main character Phil said "So I decided to teach him a lesson and let him think his bike was stolen. And I know that sounds kinda rough, but sometimes it’s a dad’s job to be the tough guy." I think both of the underlined words have almost same meaning in general. But they are seems to have different usages. Could you explain the difference between them?