diff --git a/s-day02/src/com/inmind/foreach03/Demo05.java b/s-day02/src/com/inmind/foreach03/Demo05.java
new file mode 100644
index 0000000..aae50ff
--- /dev/null
+++ b/s-day02/src/com/inmind/foreach03/Demo05.java
@@ -0,0 +1,27 @@
+package com.inmind.foreach03;
+
+import java.util.ArrayList;
+import java.util.Collection;
+
+/*
+增强for循环遍历集合
+注意：集合的foreach循环本质是迭代器，那么所有的单列集合都可以用foreach遍历
+ */
+public class Demo05 {
+    public static void main(String[] args) {
+        //单列集合的多态写法
+        Collection<Integer> cols = new ArrayList<>();
+        cols.add(1);
+        cols.add(2);
+        cols.add(3);
+        cols.add(4);
+        //遍历集合,无法使用普通for循环遍历
+        for (Integer i : cols) {
+            System.out.println(i);
+        }
+
+        for (Integer element : cols) {
+            System.out.println( element);
+        }
+    }
+}