就这样吧 还有一些bug 不改了

CDSAE3_Lian_Lian_Kan/Forms/Interface/IBack.cs

@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace CDSAE3_Lian_Lian_Kan.Forms.Interface
+{
+    public interface IBack
+    {
+        public void Back();
+    }
+}

CDSAE3_Lian_Lian_Kan/Forms/Interface/IGameMode.cs

@@ -29,7 +29,7 @@ namespace CDSAE3_Lian_Lian_Kan.Forms.Interface
         }
         public FinishType finishType { get; set; }
     }
-    public interface IGameMode : IThemeChangeable
+    public interface IGameMode : IThemeChangeable,IBack
     {
         public void TogglePause();
         public void De_pause(object sender, EventArgs e);