Marker in { } is optional. The marker name is defined as follow:
(m1, m2,{m3}) : (bodyname.markername,bodyname.markername,{bodyname.markername}).
• m1 becomes action marker and m2 becomes base marker.
• If m3 is defined, m3 becomes reference marker.
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FM
FX
FY
FZ
TM
TX
TY
TZ