diff --git a/MessageManager.Domain/DomainModel/Message.cs b/MessageManager.Domain/DomainModel/Message.cs
index d821367..54fc2c5 100644
--- a/MessageManager.Domain/DomainModel/Message.cs
+++ b/MessageManager.Domain/DomainModel/Message.cs
@@ -4,9 +4,6 @@
 **/
 
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
 
 namespace MessageManager.Domain.DomainModel
 {
@@ -19,8 +16,8 @@ public Message(string title, string content, User sendUser)
                 throw new ArgumentNullException();
             }
             this.ID = Guid.NewGuid().ToString();
-            this.Title=title;
-            this.Content=content;
+            this.Title = title;
+            this.Content = content;
             this.SendTime = DateTime.Now;
             this.State = MessageState.NoRead;
             this.SendUser = sendUser;
diff --git a/MessageManager.Domain/DomainModel/MessageState.cs b/MessageManager.Domain/DomainModel/MessageState.cs
index 402bb64..97b31b5 100644
--- a/MessageManager.Domain/DomainModel/MessageState.cs
+++ b/MessageManager.Domain/DomainModel/MessageState.cs
@@ -3,10 +3,6 @@
 * address:https://www.github.com/yuezhongxin/MessageManager
 **/
 
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
 
 namespace MessageManager.Domain.DomainModel
 {
diff --git a/MessageManager.Domain/DomainModel/User.cs b/MessageManager.Domain/DomainModel/User.cs
index 6126e28..43f5209 100644
--- a/MessageManager.Domain/DomainModel/User.cs
+++ b/MessageManager.Domain/DomainModel/User.cs
@@ -4,9 +4,6 @@
 **/
 
 using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
 
 namespace MessageManager.Domain.DomainModel
 {