Classically trained and jazzically inclined, Teresa Carroll knows her way around a song — almost any song — because she’s lived a few lyrics herself. A graduate of Thomas Jefferson High School, she studied opera in New York in the 1970s and early ’80s, but she was always drawn to the Holy Trinity — Billie, Sarah and Ella — as well as Nancy Wilson and other jazz icons. You can hear the scatting, octave-leaping, brooding echoes of these immortals in Carroll’s vivid mezzo-soprano voice, but her style’s all her own now, and that’s the essential thing. Every fourth Sunday, she sings at Shakespeare’s; every other Tuesday, she’s at the Manhattan Grill in Cherry Creek; and periodic gigs take her to the Sambuca Jazz Café, Enoteca, and Trios in Boulder. When she gets inside a ballad like “Love for Sale,” she can break your heart.