In　this　paper,　to　improve　the　gestures＇　motion　smoothness　when　synthesizing　Chinese　sign　videos,　61　kinds　of　Chinese　hand　shape　models　and　corresponding　Chinese　hand　shape　codes　are　proposed,　which　are　used　to　choose　transferring　hand　shapes　by　judging　the　fingers＇　bending　degrees　and　relationships　between　the　joined　sign　gestures　with　obvious　motion　changes.　Besides,　we　also　construct　an　extending　sign　video　database　to　synthesize　any　sentence　in　the　field　of　domain　weather　report　based　on　joining　video　clips.　©2009　IEEE.