diff --git a/pkcs8/example_test.go b/pkcs8/example_test.go
index 13ce2d3..479cc71 100644
--- a/pkcs8/example_test.go
+++ b/pkcs8/example_test.go
@@ -27,7 +27,7 @@ func ExampleMarshalPrivateKey_withoutPassword() {
 		return
 	}
 
-	// ecode to pem
+	// encode der bytes to pem
 	block := &pem.Block{Bytes: der, Type: "PRIVATE KEY"}
 	pemContent := string(pem.EncodeToMemory(block))
 	fmt.Printf("%v\n", pemContent)
@@ -131,7 +131,7 @@ func ExampleMarshalPrivateKey() {
 		return
 	}
 
-	// ecode to pem
+	// encode der bytes to pem
 	block := &pem.Block{Bytes: der, Type: "ENCRYPTED PRIVATE KEY"}
 	pemContent := string(pem.EncodeToMemory(block))
 	fmt.Printf("%v\n", pemContent)
diff --git a/pkcs8/pkcs8.go b/pkcs8/pkcs8.go
index 1ca1f50..175a4f2 100644
--- a/pkcs8/pkcs8.go
+++ b/pkcs8/pkcs8.go
@@ -400,8 +400,6 @@ func ParseSM9EncryptPrivateKey(der []byte, v ...[]byte) (*sm9.EncryptPrivateKey,
 
 // ConvertPrivateKeyToPKCS8 converts the private key into PKCS#8 format.
 // To encrypt the private key, the password of []byte type should be provided as the second parameter.
-//
-// The only supported key types are RSA and ECDSA (*rsa.PrivateKey or *ecdsa.PrivateKey for priv)
 func ConvertPrivateKeyToPKCS8(priv interface{}, v ...[]byte) ([]byte, error) {
 	var password []byte
 	if len(v) > 0 {