diff --git a/Chapters/Chapter2/chapter2.md b/Chapters/Chapter2/chapter2.md
index 59ba6e4..115e009 100644
--- a/Chapters/Chapter2/chapter2.md
+++ b/Chapters/Chapter2/chapter2.md
@@ -13,4 +13,15 @@ Output directory's default name is ''book-result'' but you can change it in the
 
 
 ![blue](figures/pharo.png width=30)
-![jlklkjlk](figures/rmod.png width=30)
\ No newline at end of file
+![jlklkjlk](figures/rmod.png width=30)
+
+
+### Example of Sync
+
+Now we can make sure that when we copy some code the checker will report to us if the code changed from the book.
+
+```sync=true&origin=Point >> #degrees
+degrees
	"Answer the angle the receiver makes with origin in degrees. right is 0; down is 90."
	| tan theta |
+	"I changed this method my friend so you should report it"
	^ x = 0
		ifTrue:
			[ y >= 0
				ifTrue: [ 90.0 ]
				ifFalse: [ 270.0 ] ]
		ifFalse:
			[ tan := y asFloat / x asFloat.
			theta := tan arcTan.
			x >= 0
				ifTrue:
					[ y >= 0
						ifTrue: [ theta radiansToDegrees ]
						ifFalse: [ 360.0 + theta radiansToDegrees ] ]
				ifFalse: [ 180.0 + theta radiansToDegrees ] ]
+```
+