diff --git a/README.md b/README.md
index e197ec6..6cc9bb4 100644
--- a/README.md
+++ b/README.md
@@ -30,7 +30,7 @@ JavaDoc https://apidoc.gitee.com/xchao/j-im/
     "chatType":"聊天类型int类型(0:未知,1:公聊,2:私聊)",
     "group_id":"群组id仅在chatType为(1)时需要,String类型",
     "content": "内容",
-    "extras" : "JSON对象格式如：{\"扩展字段名称\":\"扩展字段value\"}"
+    "extras" : "扩展字段,JSON对象格式如：{'扩展字段名称':'扩展字段value'}"
 }
 ```
 请求:COMMAND_CHAT_REQ(11) 响应:COMMAND_CHAT_RESP(12)