sentences:  By the end of the 1960s, the brothers had returned to country rock, and their 1968 album, "Roots", was hailed by some critics as "one of the finest early country-rock albums".However, by the end of the 1960s, the Everly Brothers had ceased to be hitmakers in either North America or the UK, and in 1970, following an unsuccessful live album ("The Everly Brothers Show"), their contract with Warner Bros. lapsed after ten years.They were the summer replacement hosts for Johnny Cash's television show in 1970; their variety program, "Johnny Cash Presents the Everly Brothers", was on ABC-TV and featured Linda Ronstadt and Stevie Wonder.