Basic components
1. Introduction 2. Manual components a) Configuration b) Place b.1) Neutral space b.2) Around the head b.3) In contact with the body c) Movement d) Orientation 3. Non-manual components a) Facial expression b) Torso movement c) Head position and/or movement d) Mouth gesture d.1) Imitative d.2) Compulsory component d.3) Optional component (modifier) e) Mouthing
Then we find mouth components that are a compulsory part of the sign. "Not to have" "To have" "Appropriate"