Complex sentence: By late 1968, Lewis had begun visiting the Folk and Blues clubs of New York's Greenwich Village and after witnessing a live performance by John P. Hammond at "Gerde's Folk City", he was determined to begin performing.
Split into simpler sentences: By late 1968, Lewis had begun visiting the folk and blues clubs of New York's Greenwich Village. After witnessing a performance by John P. Hammond at Gerde's Folk City, he was determined to begin performing.