diff --git a/project.godot b/project.godot
index c6c3da7..16f900f 100644
--- a/project.godot
+++ b/project.godot
@@ -9,7 +9,7 @@
 config_version=4
 
 _global_script_classes=[ {
-"base": "Reference",
+"base": "Node2D",
 "class": "MyClass",
 "language": "GDScript",
 "path": "res://script/demo02_base/MyClass.gd"
diff --git a/scene/demo02_base/Base.tscn b/scene/demo02_base/Base1.tscn
similarity index 57%
rename from scene/demo02_base/Base.tscn
rename to scene/demo02_base/Base1.tscn
index 8d9705f..4d8b651 100644
--- a/scene/demo02_base/Base.tscn
+++ b/scene/demo02_base/Base1.tscn
@@ -1,6 +1,6 @@
 [gd_scene load_steps=2 format=2]
 
-[ext_resource path="res://script/demo02_base/base.gd" type="Script" id=1]
+[ext_resource path="res://script/demo02_base/base1.gd" type="Script" id=1]
 
 [node name="Node2D" type="Node2D"]
 script = ExtResource( 1 )
diff --git a/scene/demo02_base/Base2.tscn b/scene/demo02_base/Base2.tscn
new file mode 100644
index 0000000..c624568
--- /dev/null
+++ b/scene/demo02_base/Base2.tscn
@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://script/demo02_base/base2.gd" type="Script" id=1]
+
+[node name="Node2D" type="Node2D"]
+script = ExtResource( 1 )
diff --git a/scene/demo02_base/Base3.tscn b/scene/demo02_base/Base3.tscn
new file mode 100644
index 0000000..535c212
--- /dev/null
+++ b/scene/demo02_base/Base3.tscn
@@ -0,0 +1,6 @@
+[gd_scene load_steps=2 format=2]
+
+[ext_resource path="res://script/demo02_base/base3.gd" type="Script" id=1]
+
+[node name="Node2D" type="Node2D"]
+script = ExtResource( 1 )
diff --git a/script/demo02_base/A.gd b/script/demo02_base/A.gd
new file mode 100644
index 0000000..85d4571
--- /dev/null
+++ b/script/demo02_base/A.gd
@@ -0,0 +1,4 @@
+extends Reference
+
+# 表示B对象
+var b
diff --git a/script/demo02_base/B.gd b/script/demo02_base/B.gd
new file mode 100644
index 0000000..ecab3e4
--- /dev/null
+++ b/script/demo02_base/B.gd
@@ -0,0 +1,4 @@
+extends Reference
+
+# 表示A对象
+var a
diff --git a/script/demo02_base/CNode.gd b/script/demo02_base/CNode.gd
new file mode 100644
index 0000000..06d59ed
--- /dev/null
+++ b/script/demo02_base/CNode.gd
@@ -0,0 +1,4 @@
+extends Node2D
+
+func _to_string():
+	print("This is C Node2!")
diff --git a/script/demo02_base/CReference.gd b/script/demo02_base/CReference.gd
new file mode 100644
index 0000000..be3e7ae
--- /dev/null
+++ b/script/demo02_base/CReference.gd
@@ -0,0 +1,5 @@
+# 如果没有继承任何类，则默认继承Reference
+extends Reference
+
+func _to_string():
+	print("This is C Reference!")
diff --git a/script/demo02_base/MyClass.gd b/script/demo02_base/MyClass.gd
index f1d8d87..8349c68 100644
--- a/script/demo02_base/MyClass.gd
+++ b/script/demo02_base/MyClass.gd
@@ -1,4 +1,4 @@
-# extends Node2D
+extends Node2D
 
 const StringUtils = preload("res://zfoo/util/StringUtils.gd")
 
@@ -60,7 +60,7 @@ func typeInfo():
 	print(StringUtils.format(template, [TYPE_DICTIONARY, typeof(dict), dict]))
 	print(StringUtils.format(template, [TYPE_DICTIONARY, typeof(FOOD), FOOD]))
 	print(StringUtils.format(template, [TYPE_DICTIONARY, typeof(FOOD.GOOD), FOOD.GOOD]))
-	print(self is Reference)
+	print(self is Node)
 	print(a is Dog) # 类似于instanceof
 
 func some_function(param1, param2):
diff --git a/script/demo02_base/base.gd b/script/demo02_base/base1.gd
similarity index 60%
rename from script/demo02_base/base.gd
rename to script/demo02_base/base1.gd
index 6af820a..787fcba 100644
--- a/script/demo02_base/base.gd
+++ b/script/demo02_base/base1.gd
@@ -1,5 +1,6 @@
 extends Node2D
 
+
 # Declare member variables here. Examples:
 export var a = 1
 export var b:NodePath
@@ -8,7 +9,7 @@ export(String, FILE) var e
 export(String, FILE, "*.txt") var d
 export(Resource) var f
 export(Color, RGB) var g
-var arr = []
+
 # Called when the node enters the scene tree for the first time.
 func _ready():
 	print("new一个对象--------------------------------")
@@ -36,24 +37,4 @@ func _ready():
 	print("内部类测试--------------------------------")
 	myClass.innerClassTest()
 
-	print("垃圾回收--------------------------------")
-	# 如果一个类没有指明继承哪个类，则默认继承Reference（可以被自动的垃圾回收，类似其他语言的那种垃圾回收），非常重要的知识点
-	for i in range(10000):
-		var instance = MyClass.new()
-		arr.append(instance)
-		# instance.unreference()
-		# 立即释放对象
-		# instance.free()
-		# 放在队列里，等系统统一释放对象，推荐
-		# instance.queue_free()
-	print("立即输出数组的第一位内容：")
-	var firstElement = arr[0]
-	print(arr[0])
 
-var frame = 0
-func _process(delta):
-	frame = frame + 1
-	if frame == 300:
-		print("等待一会数组的第一位内容")
-		arr[0].typeInfo()
-		print(typeof(arr[0]))
diff --git a/script/demo02_base/base2.gd b/script/demo02_base/base2.gd
new file mode 100644
index 0000000..28bc8f1
--- /dev/null
+++ b/script/demo02_base/base2.gd
@@ -0,0 +1,46 @@
+extends Node2D
+
+const CNode = preload("res://script/demo02_base/CNode.gd")
+const CReference = preload("res://script/demo02_base/CReference.gd")
+
+# monitor初探
+func _ready():
+	#nodeTest()
+	#nodeFreeTest()
+	#nodeQueueFreeTest()
+	#referenceTest()
+	#referenceFreeTest()
+	referencUnreferenceTest()
+	pass
+
+
+func nodeTest():
+	for i in range(10000):
+		var instance = CNode.new()
+
+
+func nodeFreeTest():
+	for i in range(10000):
+		var instance = CNode.new()
+		instance.free()
+
+# queue_free效率更高	
+func nodeQueueFreeTest():
+	for i in range(10000):
+		var instance = CNode.new()
+		instance.queue_free()
+		
+func referenceTest():
+	for i in range(10000):
+		var instance = CReference.new()
+
+
+func referenceFreeTest():
+	for i in range(10000):
+		var instance = CReference.new()
+		instance.free()
+
+func referencUnreferenceTest():
+	for i in range(10000):
+		var instance = CReference.new()
+		instance.unreference()
diff --git a/script/demo02_base/base3.gd b/script/demo02_base/base3.gd
new file mode 100644
index 0000000..c632014
--- /dev/null
+++ b/script/demo02_base/base3.gd
@@ -0,0 +1,39 @@
+extends Node2D
+
+const A = preload("res://script/demo02_base/A.gd")
+const B = preload("res://script/demo02_base/B.gd")
+
+func _ready():
+	#referenceTest()
+	#referenceCycleTest()
+	#referenceUnreference1Test()
+	referenceUnreference2Test()
+	pass
+
+
+func referenceTest():
+	var a = A.new()
+	var b = B.new()
+
+func referenceCycleTest():
+	var a = A.new()
+	var b = B.new()
+	a.b = b
+	b.a = a
+
+
+func referenceUnreference1Test():
+	var a = A.new()
+	var b = B.new()
+	a.b = b
+	b.a = a
+	a.unreference()
+	b.unreference()
+
+func referenceUnreference2Test():
+	var a = A.new()
+	var b = B.new()
+	a.b = b
+	b.a = a
+	a.b.unreference()
+	b.a.unreference()