diff --git a/README.md b/README.md
index 0468c33..a5483a7 100644
--- a/README.md
+++ b/README.md
@@ -56,13 +56,11 @@ func myFunc(i interface{}) {
 	n := i.(int32)
 	atomic.AddInt32(&sum, n)
 	fmt.Printf("run with %d\n", n)
-	return nil
 }
 
 func demoFunc() {
 	time.Sleep(10 * time.Millisecond)
 	fmt.Println("Hello World!")
-	return nil
 }
 
 func main() {
diff --git a/README_ZH.md b/README_ZH.md
index 4cf9541..4f691c1 100644
--- a/README_ZH.md
+++ b/README_ZH.md
@@ -55,13 +55,11 @@ func myFunc(i interface{}) {
 	n := i.(int32)
 	atomic.AddInt32(&sum, n)
 	fmt.Printf("run with %d\n", n)
-	return nil
 }
 
 func demoFunc() {
 	time.Sleep(10 * time.Millisecond)
 	fmt.Println("Hello World!")
-	return nil
 }
 
 func main() {
diff --git a/examples/main.go b/examples/main.go
index be8dfc3..23f39db 100644
--- a/examples/main.go
+++ b/examples/main.go
@@ -37,13 +37,11 @@ func myFunc(i interface{}) {
 	n := i.(int32)
 	atomic.AddInt32(&sum, n)
 	fmt.Printf("run with %d\n", n)
-	return nil
 }
 
 func demoFunc() {
 	time.Sleep(10 * time.Millisecond)
 	fmt.Println("Hello World!")
-	return nil
 }
 
 func main() {