sentences:  TCM recognizes twenty meridians, cutaneous and subcutaneous in nature, which have branching sub-meridians believed to affect surrounding tissues.Twelve of these major meridians, commonly referred to as "the primary meridians", are bilateral and are associated with internal organs.The remaining eight meridians are designated as "extraordinary", and are also bilateral except for three, one that encircles the body near the waist, and two that run along the midline of the body.