U2 and the Rolling Stones are among the bands that (1) ... worldwide tours in recent years. Tickets were sold out within minutes, and the bands performed for audiences of hundreds of thousands of people. Tours don’t just happen overnight. When a band (2) ... to put on a new show, preparations can go on for months. Among the things that have to be created are the special effects that (3) ... in most big rock shows these days, and the videos that are screened before and during the show. These bands are determined that their fans (4) ... the concert a letdown, so they work hard to make sure to give concerts that are worth seeing.