Hello val; Thank you very much for the replay. Its very clear and useful. So now I understand that in SW, it uses diagonal planes at times but not as often as other two planes. Thanks you Gan >>> "Valerie Sutton" 02/09/10 5:38 PM >>> SignWriting List September 2, 2010 > On Sep 2, 2010, at 3:36 AM, Gan Lu wrote: > Just a quick question. For the hand movement in sign writing, apart from the wall and floor plane, there is another diagonal plane also. How important the diagonal plane is in sign language? As there seems only a subtle information about it. Many thanks, Gan Hello Gan! Thank you for this question...I appreciate it, that you posted your question to the SignWriting List, as this helps all the readers on the LIst ;-) Hands do go on Diagonal planes at times in sign languages, although not as often as the hands parallel to the Wall or Floor. The Diagonal hands are usually followed by a diagonal movement. Regarding planes in SignWriting... There are two things you need to know...how the Diagonal Planes relate to Movement Symbols and how they relate to Hands, because they are dependent on each other to write sign languages. 1. The Wall Plane and the Floor Plane are used throughout all of SignWriting, for both Hand Symbols and Movement Arrows. 2. When writing Movement Arrows, we do have the Up-Forward Diagonal Plane, the Down-Forward Diagonal Plane, the Up-Back Diagonal Plane and the Down-Back Diagonal Plane, but those Movement Arrows are not used as often as the Wall and Floor Planes.