diff --git a/README.md b/README.md
index e26fa67..cae54a6 100644
--- a/README.md
+++ b/README.md
@@ -183,6 +183,9 @@ import (
 
 func main() {
   bitmap := robotgo.CaptureScreen(10, 20, 30, 40)
+  // use `defer robotgo.FreeBitmap(bit)` to free the bitmap
+  defer robotgo.FreeBitmap(bitmap)
+
   fmt.Println("...", bitmap)
 
   fx, fy := robotgo.FindBitmap(bitmap)
diff --git a/README_zh.md b/README_zh.md
index 828a35c..b1279a2 100644
--- a/README_zh.md
+++ b/README_zh.md
@@ -181,6 +181,8 @@ import (
 
 func main() {
   bitmap := robotgo.CaptureScreen(10, 20, 30, 40)
+  // use `defer robotgo.FreeBitmap(bit)` to free the bitmap
+  defer robotgo.FreeBitmap(bitmap)
   fmt.Println("...", bitmap)
 
   fx, fy := robotgo.FindBitmap(bitmap)
diff --git a/examples/README.md b/examples/README.md
index 7d3bbf2..9e6f5d8 100644
--- a/examples/README.md
+++ b/examples/README.md
@@ -87,6 +87,8 @@ import (
 
 func main() {
   bitmap := robotgo.CaptureScreen(10, 20, 30, 40)
+  // use `defer robotgo.FreeBitmap(bit)` to free the bitmap
+  defer robotgo.FreeBitmap(bitmap)
   fmt.Println("...", bitmap)
 
   fx, fy := robotgo.FindBitmap(bitmap)
diff --git a/robotgo.go b/robotgo.go
index 86fee72..d0148e9 100644
--- a/robotgo.go
+++ b/robotgo.go
@@ -254,7 +254,7 @@ func GetXDisplayName() string {
 	return gname
 }
 
-// CaptureScreen capture the screen return bitmap(c struct)
+// CaptureScreen capture the screen return bitmap(c struct),
 // use `defer robotgo.FreeBitmap(bitmap)` to free the bitmap
 func CaptureScreen(args ...int) C.MMBitmapRef {
 	var x, y, w, h C.size_t
@@ -798,7 +798,7 @@ func internalFindBitmap(bit, sbit C.MMBitmapRef, tolerance float64) (int, int) {
 //
 //  |tolerance| should be in the range 0.0f - 1.0f, denoting how closely the
 //  colors in the bitmaps need to match, with 0 being exact and 1 being any.
-// 
+//
 // This method only automatically free the internal bitmap,
 // use `defer robotgo.FreeBitmap(bit)` to free the bitmap
 func FindBitmap(bit C.MMBitmapRef, args ...interface{}) (int, int) {