diff --git a/README.md b/README.md
index 1967ab6..fc4e4ea 100644
--- a/README.md
+++ b/README.md
@@ -91,9 +91,9 @@ type Config struct {
 }
 
 func main() {
-	_ = os.Setenv("API_HOST", "127.0.0.1")
-	_ = os.Setenv("API_PORT", "8080")
-	_ = os.Setenv("API_PASSWORD", "test")
+	_ = os.Setenv("API_ES_HOST", "127.0.0.1")
+	_ = os.Setenv("API_ES_PORT", "8080")
+	_ = os.Setenv("API_ES_PASSWORD", "test")
 
 	var cfg Config
 	loader := env.New("API_", log.Printf)
diff --git a/example_test.go b/example_test.go
index de26502..4d7315d 100644
--- a/example_test.go
+++ b/example_test.go
@@ -3,12 +3,14 @@ package env_test
 import (
 	"fmt"
 	"github.com/qiangxue/go-env"
+	"log"
 	"os"
 )
 
 type Config struct {
 	Host string
 	Port int
+	Password string `env:",secret"`
 }
 
 func Example_one() {
@@ -25,3 +27,22 @@ func Example_one() {
 	// 127.0.0.1
 	// 8080
 }
+
+func Example_two() {
+	_ = os.Setenv("API_HOST", "127.0.0.1")
+	_ = os.Setenv("API_PORT", "8080")
+	_ = os.Setenv("API_PASSWORD", "test")
+
+	var cfg Config
+	loader := env.New("API_", log.Printf)
+	if err := loader.Load(&cfg); err != nil {
+		panic(err)
+	}
+	fmt.Println(cfg.Host)
+	fmt.Println(cfg.Port)
+	fmt.Println(cfg.Password)
+	// Output:
+	// 127.0.0.1
+	// 8080
+	// test
+}