diff --git a/Convention/[Symbolization]/Detail/Exception.cs b/Convention/[Symbolization]/Detail/Exception.cs
new file mode 100644
index 0000000..465b0d2
--- /dev/null
+++ b/Convention/[Symbolization]/Detail/Exception.cs
@@ -0,0 +1,16 @@
+using System;
+
+namespace Convention.Symbolization
+{
+
+	[Serializable]
+	public class InvalidGrammarException : Exception
+	{
+		public InvalidGrammarException() { }
+		public InvalidGrammarException(string message) : base(message) { }
+		public InvalidGrammarException(string message, Exception inner) : base(message, inner) { }
+		protected InvalidGrammarException(
+		  System.Runtime.Serialization.SerializationInfo info,
+		  System.Runtime.Serialization.StreamingContext context) : base(info, context) { }
+	}
+}
diff --git a/Convention/[Symbolization]/Internal/Functional.cs b/Convention/[Symbolization]/Detail/Functional.cs
similarity index 100%
rename from Convention/[Symbolization]/Internal/Functional.cs
rename to Convention/[Symbolization]/Detail/Functional.cs
diff --git a/Convention/[Symbolization]/Detail/Keyword.cs b/Convention/[Symbolization]/Detail/Keyword.cs
new file mode 100644
index 0000000..55c99ac
--- /dev/null
+++ b/Convention/[Symbolization]/Detail/Keyword.cs
@@ -0,0 +1,101 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Convention.Symbolization.Internal
+{
+    public abstract class Keyword : Variable
+    {
+        protected Keyword(string keyword, Type realType) : base(new(keyword, realType))
+        {
+            Keywords.Add(keyword, this);
+        }
+
+        public static readonly Dictionary<string, Keyword> Keywords = new();
+
+        public abstract SymbolizationContext Execute(SymbolizationContext context, Variable[] leftParameters, Variable[] rightParameters);
+
+        public override string ToString()
+        {
+            return SymbolInfo.SymbolName;
+        }
+    }
+
+    public abstract class Keyword<T> : Keyword where T:Keyword<T>,new()
+    {
+        private static T MyInstance = new();
+
+        public static T Instance
+        {
+            get
+            {
+                return MyInstance;
+            }
+        }
+
+        protected Keyword(string keyword) : base(keyword, typeof(T))
+        {
+        }
+
+        public override bool Equals(Variable other)
+        {
+            return MyInstance == other;
+        }
+    }
+
+}
+
+namespace Convention.Symbolization.Keyword
+{
+    public sealed class ExitScope : Internal.Keyword<ExitScope>
+    {
+        public ExitScope() : base("__exit_scope__")
+        {
+        }
+
+        public override SymbolizationContext Execute(SymbolizationContext context, Internal.Variable[] leftParameters, Internal.Variable[] rightParameters)
+        {
+            context.CurrentNamespace.EndAndTApplyUpdate();
+            return context.ParentContext;
+        }
+    }
+
+    public sealed class Namespace : Internal.Keyword<Namespace>
+    {
+        public Namespace() : base("namespace")
+        {
+        }
+        public override SymbolizationContext Execute(SymbolizationContext context, Internal.Variable[] leftParameters, Internal.Variable[] rightParameters)
+        {
+            if (leftParameters.Length != 0)
+                throw new InvalidGrammarException($"{this}: has invalid subject");
+            if (rightParameters.Length != 1)
+                throw new InvalidGrammarException($"{this}: needs to have one and only one object");
+            Internal.Namespace subNamespace = context.CurrentNamespace.CreateOrGetSubNamespace(rightParameters[0].ToString());
+            subNamespace.BeginUpdate();
+            SymbolizationContext subContext = new(context, subNamespace);
+            return subContext;
+        }
+    }
+
+    public sealed class Structure : Internal.Keyword<Structure>
+    {
+        public Structure() : base("struct")
+        {
+        }
+
+        public override SymbolizationContext Execute(SymbolizationContext context, Internal.Variable[] leftParameters, Internal.Variable[] rightParameters)
+        {
+            if (leftParameters.Length != 0)
+                throw new InvalidGrammarException($"{this}: has invalid subject");
+            if (rightParameters.Length != 1)
+                throw new InvalidGrammarException($"{this}: needs to have one and only one object");
+            Internal.Namespace subNamespace = context.CurrentNamespace.CreateOrGetSubNamespace(rightParameters[0].ToString());
+            subNamespace.BeginUpdate();
+            SymbolizationContext subContext = new(context, subNamespace);
+            return subContext;
+        }
+    }
+}
diff --git a/Convention/[Symbolization]/Internal/Modification.cs b/Convention/[Symbolization]/Detail/Modification.cs
similarity index 100%
rename from Convention/[Symbolization]/Internal/Modification.cs
rename to Convention/[Symbolization]/Detail/Modification.cs
diff --git a/Convention/[Symbolization]/Internal/Namespace.cs b/Convention/[Symbolization]/Detail/Namespace.cs
similarity index 99%
rename from Convention/[Symbolization]/Internal/Namespace.cs
rename to Convention/[Symbolization]/Detail/Namespace.cs
index b5a66d5..ac16fb3 100644
--- a/Convention/[Symbolization]/Internal/Namespace.cs
+++ b/Convention/[Symbolization]/Detail/Namespace.cs
@@ -45,7 +45,7 @@ namespace Convention.Symbolization.Internal
             Structures.Add(structure.SymbolInfo.SymbolName, structure);
         }
 
-        public void EndAndApplyUpdate()
+        public void EndAndTApplyUpdate()
         {
             Updateable--;
             if (Updateable == 0)
diff --git a/Convention/[Symbolization]/Detail/PrimitiveType.cs b/Convention/[Symbolization]/Detail/PrimitiveType.cs
new file mode 100644
index 0000000..90a5a3f
--- /dev/null
+++ b/Convention/[Symbolization]/Detail/PrimitiveType.cs
@@ -0,0 +1,53 @@
+using System;
+
+namespace Convention.Symbolization.Primitive
+{
+    public class PrimitiveType<T> : Internal.Variable
+    {
+        public PrimitiveType() : base(new(typeof(T).Name, typeof(T)))
+        {
+        }
+
+        public override bool Equals(Internal.Variable other)
+        {
+            return other is PrimitiveType<T>;
+        }
+
+        public virtual T CloneValue(T value)
+        {
+            if (Utility.IsNumber(typeof(T)))
+                return value;
+            else if (Utility.IsString(typeof(T)))
+                return (T)(object)new string((string)(object)value);
+            else if (value is ICloneable cloneable)
+                return (T)cloneable.Clone();
+            else if (value is Internal.Variable)
+                return value;
+            return value;
+        }
+
+        public virtual T DefaultValue() => default;
+    }
+
+    public class PrimitiveInstance<T> : Internal.CloneableVariable<PrimitiveInstance<T>>
+    {
+        private readonly PrimitiveType<T> MyPrimitiveType = new();
+        public T Value;
+
+        public PrimitiveInstance(string symbolName, T value, PrimitiveType<T> primitiveType) : base(symbolName)
+        {
+            this.Value = value;
+            this.MyPrimitiveType = primitiveType;
+        }
+
+        public override PrimitiveInstance<T> CloneVariable(string targetSymbolName)
+        {
+            return new(targetSymbolName, MyPrimitiveType.CloneValue(this.Value), this.MyPrimitiveType);
+        }
+
+        public override bool Equals(PrimitiveInstance<T> other)
+        {
+            return this.Value.Equals(other.Value);
+        }
+    }
+}
diff --git a/Convention/[Symbolization]/Detail/Reader.cs b/Convention/[Symbolization]/Detail/Reader.cs
new file mode 100644
index 0000000..1b022e1
--- /dev/null
+++ b/Convention/[Symbolization]/Detail/Reader.cs
@@ -0,0 +1,13 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace Convention.Symbolization.Internal
+{
+    public class SymbolizationReader
+    {
+
+    }
+}
diff --git a/Convention/[Symbolization]/Internal/Structure.cs b/Convention/[Symbolization]/Detail/Structure.cs
similarity index 100%
rename from Convention/[Symbolization]/Internal/Structure.cs
rename to Convention/[Symbolization]/Detail/Structure.cs
diff --git a/Convention/[Symbolization]/Internal/Variable.cs b/Convention/[Symbolization]/Detail/Variable.cs
similarity index 100%
rename from Convention/[Symbolization]/Internal/Variable.cs
rename to Convention/[Symbolization]/Detail/Variable.cs
diff --git a/Convention/[Symbolization]/Symbolization.cs b/Convention/[Symbolization]/Symbolization.cs
index 03b27f4..44c6f16 100644
--- a/Convention/[Symbolization]/Symbolization.cs
+++ b/Convention/[Symbolization]/Symbolization.cs
@@ -8,7 +8,17 @@ namespace Convention.Symbolization
 {
     public class SymbolizationContext
     {
+        public SymbolizationContext() : this(null, Internal.Namespace.CreateRootNamespace()) { }
+        public SymbolizationContext(SymbolizationContext parent) : this(parent, parent.CurrentNamespace) { }
+        public SymbolizationContext(SymbolizationContext parent, Internal.Namespace newNamespace)
+        {
+            this.ParentContext = parent;
+            this.CurrentNamespace = newNamespace;
+        }
 
+        public readonly SymbolizationContext ParentContext;
+        public readonly Dictionary<string, Internal.Variable> Variables = new();
+        public readonly Internal.Namespace CurrentNamespace;
     }
 
     public class SymbolizationRunner
@@ -23,5 +33,18 @@ namespace Convention.Symbolization
         }
         public SymbolizationRunner() :this(new()){ }
 
+        public Exception Compile()
+        {
+            try
+            {
+
+            }
+            catch (Exception ex)
+            {
+                return ex;
+            }
+            return null;
+        }
+
     }
 }