consider following example:
考虑以下示例：
<root>
<instruments>
<flute>
<baz>bazik</baz>
</flute>
<guitar>
<deep>
<baz>more bazik</baz>
</deep>
</guitar>
<drum>
<foo>fooled</foo>
</drum>
</instruments>
</root>
<root>
