diff --git a/HISTORY b/HISTORY
index a636133..2ec1b3d 100755
--- a/HISTORY
+++ b/HISTORY
@@ -1,3 +1,6 @@
+Dec. 31 2015
+Added a new sample script source file
+
 Dec. 30 2015
 Improved error handling with sub routine and class
 Implemented DIR command
diff --git a/clean.cmd b/clean.cmd
index ecff3e2..433c2a0 100644
--- a/clean.cmd
+++ b/clean.cmd
@@ -1,21 +1,25 @@
 @echo off
 echo Cleaning, a moment please...
 
+rd /s /q .vs
+rd /s /q temp
+
 attrib *.suo -s -r -h
+
+del /f /s /q *.exp
+del /f /s /q *.log
 del /f /s /q *.ncb
+del /f /s /q *.obj
+del /f /s /q *.pdb
 del /f /s /q *.sdf
 del /f /s /q *.suo
 del /f /s /q *.user
 
-rd /s /q temp
-
 del /f /s /q output\*.dep
 del /f /s /q output\*.htm
 del /f /s /q output\*.idb
 del /f /s /q output\*.ilk
 del /f /s /q output\*.manifest
-del /f /s /q output\*.obj
-del /f /s /q output\*.pdb
 del /f /s /q output\*.res
 del /f /s /q output\my_basic_d.exe
 
diff --git a/my_basic.vcproj b/my_basic.vcproj
index a0f8232..917d5f5 100755
--- a/my_basic.vcproj
+++ b/my_basic.vcproj
@@ -309,6 +309,26 @@
 					/>
 				</FileConfiguration>
 			</File>
+			<File
+				RelativePath=".\sample\sample06.bas"
+				>
+				<FileConfiguration
+					Name="debug|Win32"
+					ExcludedFromBuild="true"
+					>
+					<Tool
+						Name="VCCustomBuildTool"
+					/>
+				</FileConfiguration>
+				<FileConfiguration
+					Name="release|Win32"
+					ExcludedFromBuild="true"
+					>
+					<Tool
+						Name="VCCustomBuildTool"
+					/>
+				</FileConfiguration>
+			</File>
 		</Filter>
 		<Filter
 			Name="res"
diff --git a/sample/sample06.bas b/sample/sample06.bas
new file mode 100644
index 0000000..f900a02
--- /dev/null
+++ b/sample/sample06.bas
@@ -0,0 +1,27 @@
+' This script is an example of MY-BASIC
+' Copyright (c) 2011 - 2016 Wang Renxin. All rights reserved.
+' For more information, see https://github.com/paladin-t/my_basic/
+
+class animal
+    def speak(a)
+        print "default" + a;
+    enddef
+endclass
+
+class cat(animal)
+    def speak(a)
+        print "meow" + a;
+    enddef
+endclass
+
+class dog(animal)
+    def speak(a)
+        print "bark" + a;
+    enddef
+endclass
+
+c = new(cat)
+d = new(dog)
+
+c.speak("!")
+d.speak("!")
\ No newline at end of file