 Some composers, like Dvořák and Smetana, have used folk themes to impart a nationalist flavor to their work, while others like Bartók have used specific themes lifted whole from their folk-music origins.Certain staples of classical music are often used commercially (either in advertising or in movie soundtracks).In television commercials, several passages have become clichéd, particularly the opening of Richard Strauss' "Also sprach Zarathustra" (made famous in the film "") and the opening section "O Fortuna" of Carl Orff's "Carmina Burana"; other examples include the "Dies irae" from the Verdi Requiem, Edvard Grieg's "In the Hall of the Mountain King" from "Peer Gynt", the opening bars of Beethoven's Symphony No.