question: What were some hard rock bands of the 1970s ?
answer: Led Zeppelin , The Who , Deep Purple , Aerosmith , AC/DC and Van Halen
turker_answer: Led Zeppelin , The Who , Deep Purple , Aerosmith , AC/DC and Van Halen are some hard rock bands of the 1970 's .
rule-based: Some hard rock bands of the 1970s were led Zeppelin , The Who , Deep Purple , Aerosmith , AC/DC and Van Halen .