Skill Builder: 4 Chord Easy Strum + add a thumb exercise View course details About This Course Level: Beginner Learn a skill building 4 chord exercise that incorporates a thumb technique into the strum. Course Information Categories: Mini-Course, Skill Builder, Strumming Exercises Course Instructor KEV Author 4 Chord Easy Strum + Add a Thumb exercise Learn the 4-chord Easy Strum + add a Thumb Exercise Course Information Categories: Mini-Course, Skill Builder, Strumming Exercises