Complex sentence: In 1973, she debuted as Kasuga Harumi and tried to become a pop idol with the release of with the songs "Shinjuku Tenshin" and "Kantsubaki no Shima Kara".
Split into simpler sentences: In 1973, she debuted as Kasuga Harumi with the song "Shinjuku Tenshin". She later tried to become an idol with the release of "Kantsubaki no Shima Kara".