diff --git a/internal/header.go b/internal/header.go
index 7a6a045..91ae004 100644
--- a/internal/header.go
+++ b/internal/header.go
@@ -170,20 +170,22 @@ func matchShebang(b []byte) []byte {
 	return nil
 }
 
-func assemble(line, header, content []byte, isUpdate bool) []byte {
-	if line != nil {
-		// line, content
-		// get content exclude the first line
+func assemble(shebang, header, content []byte, isUpdate bool) []byte {
+	if shebang != nil {
 		if !isUpdate {
-			content = content[len(line):]
+			// get content exclude the shebang
+			content = content[len(shebang):]
 		}
-		// add \n if the first line do not end with \n
-		if line[len(line)-1] != '\n' {
-			line = append(line, '\n')
+
+		// add \n if the shebang do not end with \n
+		if shebang[len(shebang)-1] != '\n' {
+			shebang = append(shebang, '\n')
 		}
-		header = append(line, header...)
+		header = append(shebang, header...)
 	}
-	// line, header, content
+	// 1. shebang
+	// 2. header
+	// 3. content
 	header = append(header, content...)
 	return header
 }
diff --git a/internal/operation.go b/internal/operation.go
index 5b9d769..d0959a1 100644
--- a/internal/operation.go
+++ b/internal/operation.go
@@ -196,14 +196,15 @@ func operationUpdate(path string, d fs.DirEntry, header []byte) func() {
 			return
 		}
 
-		// get the first line of the special file
-		line := matchShebang(content)
+		// get the shebang of the special file
+		shebang := matchShebang(content)
 		file, err := os.Open(path)
 		if err != nil {
 			counter.failed++
 			slog.Error("open file error", slog.String("path", path), slog.String("err", err.Error()))
 			return
 		}
+
 		scanner := bufio.NewScanner(file)
 		for scanner.Scan() {
 			l := scanner.Bytes()
@@ -211,6 +212,7 @@ func operationUpdate(path string, d fs.DirEntry, header []byte) func() {
 				break
 			}
 		}
+
 		afterBlankLine := make([]byte, 0)
 		// NOTE: scanner will not scan from the beginning
 		for scanner.Scan() {
@@ -221,8 +223,10 @@ func operationUpdate(path string, d fs.DirEntry, header []byte) func() {
 		if err != nil {
 			slog.Error("file close error")
 		}
+
 		// assemble license header and modify the file
-		b := assemble(line, header, afterBlankLine, true)
+		b := assemble(shebang, header, afterBlankLine, true)
+
 		err = os.WriteFile(path, b, d.Type())
 		if err != nil {
 			counter.failed++
@@ -293,10 +297,11 @@ func operationAdd(path string, d fs.DirEntry, header []byte) func() {
 			return
 		}
 
-		// get the first line of the special file
-		line := matchShebang(content)
+		// get the shebang of the special file
+		shebang := matchShebang(content)
 		// assemble license header and modify the file
-		b := assemble(line, header, content, false)
+		b := assemble(shebang, header, content, false)
+
 		err = os.WriteFile(path, b, d.Type())
 		if err != nil {
 			counter.failed++