diff --git a/sm2/sm2.go b/sm2/sm2.go
index 984d917..177116a 100644
--- a/sm2/sm2.go
+++ b/sm2/sm2.go
@@ -604,7 +604,7 @@ func (z *zr) Read(dst []byte) (n int, err error) {
 
 var zeroReader = &zr{}
 
-// IsSM2PublicKey check if given public key is SM2 public key or not
+// IsSM2PublicKey check if given public key is a SM2 public key or not
 func IsSM2PublicKey(publicKey interface{}) bool {
 	pub, ok := publicKey.(*ecdsa.PublicKey)
 	return ok && strings.EqualFold(P256().Params().Name, pub.Curve.Params().Name)