diff --git a/doc/sandbox.mdwn b/doc/sandbox.mdwn
index 2813486c7..9e7700e23 100644
--- a/doc/sandbox.mdwn
+++ b/doc/sandbox.mdwn
@@ -14,7 +14,7 @@ There are Polish diacritical characters: ą, ć, ę, ł, ń, ó, ś, ż, ź.
 
 Korean characters test : 한글테스트입니다.
 
-測試 
+測試 c测试
 
 test edit