diff --git a/node.go b/node.go
index 24b7259..d0e6a54 100644
--- a/node.go
+++ b/node.go
@@ -68,10 +68,16 @@ func (n *Node) InnerText() string {
 }
 
 func outputXML(buf *bytes.Buffer, n *Node) {
-	if n.Type == TextNode || n.Type == CommentNode {
+	if n.Type == TextNode {
 		xml.EscapeText(buf, []byte(strings.TrimSpace(n.Data)))
 		return
 	}
+	if n.Type == CommentNode {
+		buf.WriteString("<!--")
+		buf.WriteString(n.Data)
+		buf.WriteString("-->")
+		return
+	}
 	if n.Type == DeclarationNode {
 		buf.WriteString("<?" + n.Data)
 	} else {
@@ -258,6 +264,11 @@ func parse(r io.Reader) (*Node, error) {
 				addSibling(prev, node)
 			} else if level > prev.level {
 				addChild(prev, node)
+			} else if level < prev.level {
+				for i := prev.level - level; i > 1; i-- {
+					prev = prev.Parent
+				}
+				addSibling(prev.Parent, node)
 			}
 		case xml.ProcInst: // Processing Instruction
 			if prev.Type != DeclarationNode {
diff --git a/node_test.go b/node_test.go
index c046c24..1936958 100644
--- a/node_test.go
+++ b/node_test.go
@@ -317,3 +317,30 @@ func TestAttributeWithNamespace(t *testing.T) {
 		t.Fatal("n is nil")
 	}
 }
+
+func TestOutputXMLWithCommentNode(t *testing.T) {
+	s := `<?xml version="1.0" encoding="utf-8"?>
+	<!-- Students grades are updated bi-monthly -->
+	<class_list>
+		<student>
+			<name>Robert</name>
+			<grade>A+</grade>
+		</student>
+	<!--
+		<student>
+			<name>Lenard</name>
+			<grade>A-</grade>
+		</student> 
+	-->
+	</class_list>`
+	doc, _ := Parse(strings.NewReader(s))
+	t.Log(doc.OutputXML(true))
+	if e, g := "<!-- Students grades are updated bi-monthly -->", doc.OutputXML(true); strings.Index(g, e) == -1 {
+		t.Fatal("missing some comment-node.")
+	}
+	n := FindOne(doc, "//class_list")
+	t.Log(n.OutputXML(false))
+	if e, g := "<name>Lenard</name>", n.OutputXML(false); strings.Index(g, e) == -1 {
+		t.Fatal("missing some comment-node")
+	}
+}