[originaltext]　　(20) Americans are more "down the line. " They don’t hide their

　　(20) Americans are more "down the line. " They don’t hide their hopes and fears. They applaud ambition and openly reward success. Britons are more comfortable with life’s losers. We embrace the underdog until it’s no longer the underdog. We like to bring authority down a peg or two, just for the hell of it. Americans say "have a nice day" whether they mean it or not. Britons are terrified to say this. We tell ourselves it’s because we don’t want to sound insincere, but I think it might be for the opposite reason. (21) We don’t want to celebrate anything too soon, especially success. Failure and disappointment is always around the corner. This is due to our upbringing. Americans are brought up to believe they can be the next President of the United States. Britons are told, "It won’t happen to you." There’s a received wisdom in the UK that Americans don’t get irony. This is of course not true. But what is true is that they don’t use it all the time. It shows up in the smarter comedies but Americans don’t use it as much socially as Britons. We use it as liberally as pre-positions in everyday speech. We tease our friends. We use sarcasm as a shield and a weapon. We avoid sincerity until it’s absolutely necessary. We mercilessly take the piss out of people we like or dislike basically. Our brashness and swagger is laden with equal portions of self-deprecation.
　　20. What does the speaker think of most Americans?
　　21. What do Britons do when they face success?
　　22. What’s the main idea of this passage?