Premise: "Toi, la musique et moi" (English translation: "You, the Music and I") was the Monegasque entry in the Eurovision Song Contest 1976, performed in French by French singer Mary Christy. Christy recorded the song in five languages; French, Italian (as "La musica e noi due"), Spanish ("La música, tú y yo"), German ("Die Musik und ich") and English ("Thank You for Rushing into My Life").
Hypothesis: Mary Christy is fluent in 5 languages.