on earth片語KK [ɑn ɝθ] /ɑn ɝθ/發音片語1究竟、到底用於疑問詞後加強語氣What on earth were you thinking when you said that?你說那句話時究竟在想什麼?2天底下、世界上用於最高級或否定後加強語氣This is the most beautiful beach on earth.這是天底下最美的海灘。3在世上、在人間Life on earth began billions of years ago.地球上的生命始於數十億年前。