diff --git a/Demo/Data/LocalData/LocalStaticData.cs b/Demo/Data/LocalData/LocalStaticData.cs
index aebb784..92c7f91 100644
--- a/Demo/Data/LocalData/LocalStaticData.cs
+++ b/Demo/Data/LocalData/LocalStaticData.cs
@@ -10,7 +10,7 @@ namespace Demo.Data.LocalData
 {
     public static class LocalStaticData
     {
-        public static IEnumerable<GroupLocalEntity> groups => new List<GroupLocalEntity>
+        public static List<GroupLocalEntity> groups => new List<GroupLocalEntity>
         
         {
             new GroupLocalEntity{ Id = 1, Name = "ИП1-21" },
diff --git a/Demo/Data/Repository/GroupRepositoryImpl.cs b/Demo/Data/Repository/GroupRepositoryImpl.cs
new file mode 100644
index 0000000..e5b9a29
--- /dev/null
+++ b/Demo/Data/Repository/GroupRepositoryImpl.cs
@@ -0,0 +1,15 @@
+using Demo.Data.LocalData;
+using Demo.domain.Models;
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Demo.Data.Repository
+{
+    public class GroupRepositoryImpl
+    {
+       public List<GroupLocalEntity> GetAllGroups() => LocalStaticData.groups;
+    }
+}
diff --git a/Demo/Data/Repository/UserRepositoryImpl.cs b/Demo/Data/Repository/UserRepositoryImpl.cs
index 9d802fd..93fab95 100644
--- a/Demo/Data/Repository/UserRepositoryImpl.cs
+++ b/Demo/Data/Repository/UserRepositoryImpl.cs
@@ -10,7 +10,7 @@ namespace Demo.Data.Repository
 {
     public class UserRepositoryImpl
     {
-        public IEnumerable<UserLocalEnity> GetAllUsers() => LocalStaticData.users;
+        public List<UserLocalEnity> GetAllUsers() => LocalStaticData.users;
 
         public bool RemoveUserByGuid(Guid userGuid)
         {
@@ -31,7 +31,7 @@ namespace Demo.Data.Repository
             return userLocal;
         }
 
-        public UserLocalEnity? UpdateUserByGuid(UserLocalEnity userUpdateLocalEnity) {
+        public UserLocalEnity? UpdateUser(UserLocalEnity userUpdateLocalEnity) {
             UserLocalEnity? userLocal = LocalStaticData
                     .users
                     .Where(x => x.Guid == userUpdateLocalEnity.Guid).FirstOrDefault();
diff --git a/Demo/Domain/UseCase/UserUseCase.cs b/Demo/Domain/UseCase/UserUseCase.cs
index b98a077..f0a507d 100644
--- a/Demo/Domain/UseCase/UserUseCase.cs
+++ b/Demo/Domain/UseCase/UserUseCase.cs
@@ -1,4 +1,5 @@
 using Demo.Data.Repository;
+using Demo.domain.Models;
 using System;
 using System.Collections.Generic;
 using System.Linq;
@@ -9,12 +10,34 @@ namespace Demo.Domain.UseCase
 {
     public class UserUseCase
     {
-        private UserRepositoryImpl _repositoryImpl;
+        private UserRepositoryImpl _repositoryUserImpl;
+        private GroupRepositoryImpl _repositoryGroupImpl;
 
-        public UserUseCase(UserRepositoryImpl repositoryImpl)
+        public UserUseCase(UserRepositoryImpl repositoryImpl, GroupRepositoryImpl repositoryGroupImpl)
         {
-            _repositoryImpl = repositoryImpl;
+            _repositoryUserImpl = repositoryImpl;
+            _repositoryGroupImpl = repositoryGroupImpl;
         }
 
+      public List<Group> GetAllGroups() => _repositoryGroupImpl.GetAllGroups()
+            .Select(it => new Group { Id  = it.Id, Name = it.Name}).ToList();
+      public List<User> GetAllUsers => _repositoryUserImpl.GetAllUsers()
+            .Join(_repositoryGroupImpl.GetAllGroups(),
+            user => user.GroupID,
+            group => group.Id,
+            (user, group) => 
+            new User { FIO = user.FIO, 
+                Guid = user.Guid, 
+                Group = new Group {Id = group.Id, Name = group.Name } }
+          ).ToList();
+
+        public User UpdateUser(User user) {
+            UserLocalEnity userLocalEnity = new UserLocalEnity { FIO = user.FIO, GroupID = user.Group.Id, Guid = user.Guid };
+            UserLocalEnity? result = _repositoryUserImpl.UpdateUser(userLocalEnity);
+            if (result == null) throw new Exception("");
+            Group? group = GetAllGroups().FirstOrDefault(it => it.Id == result!.GroupID);
+            if (group == null) throw new Exception("");
+            return new User { FIO = user.FIO, Guid = user.Guid,  Group = group};
+        }
     }
 }
diff --git a/Demo/Program.cs b/Demo/Program.cs
index 5f28270..da2898d 100644
--- a/Demo/Program.cs
+++ b/Demo/Program.cs
@@ -1 +1,20 @@
-
\ No newline at end of file
+
+
+using Demo.Data.Repository;
+using Demo.domain.Models;
+using Demo.Domain.UseCase;
+
+GroupRepositoryImpl groupRepositoryImpl = new GroupRepositoryImpl();
+UserRepositoryImpl userRepositoryImpl = new UserRepositoryImpl();
+UserUseCase userUseCase = new UserUseCase(userRepositoryImpl, groupRepositoryImpl);
+
+List<User> users = userUseCase.GetAllUsers;
+
+foreach (var user in users) {
+    Console.WriteLine($"{user.FIO} группа {user.Group.Name}");
+}
+
+userUseCase.
+
+
+Console.ReadKey();
\ No newline at end of file