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Besides singing Madonna has the ability to play several musical instruments. She learned to play drum and guitar from her then-boyfriend Dan Gilroy in the late 1970s before joining the Breakfast Club line-up as the drummer. This helped her to form the band Emmy, where she performed as the guitarist and lead vocalist. Madonna later played guitar on her demo recordings. On the liner notes of Pre-Madonna, Stephen Bray wrote: "I've always thought she passed up a brilliant career as a rhythm guitarist." After her career breakthrough, Madonna focused mainly in singing but was also credited for playing cowbell on Madonna (1983) and synthesizer on Like a Prayer (1989). In 1999, Madonna had studied for three months to play the violin for the role as a violin teacher in the film Music of the Heart, before eventually leaving the project. After two decades, Madonna decided to perform with guitar again during the promotion of Music (2000). She took further lessons from guitarist Monte Pittman to improve her guitar skill. Since then Madonna has played guitar on every tour, as well as her studio albums. At the 2002 Orville H. Gibson Guitar Awards, she received nomination for Les Paul Horizon Award, which honors the most promising up-and-coming guitarist.

What instrument does Madonna play on her demo recordings?
guitar