$ xmllint --format --pretty 1 sample_txt.xml
<?xml version="1.0" encoding="ISO-8859-1"?>
<root>
  <para>
    <pnum>1</pnum>
    <ptext>This is a sample of a very specific text <emph>called</emph> <term>description</term> which has 2 subtypes: <list><item><term>1.</term><p>precise</p></item><item><term>2.</term><p>fuzzy</p></item></list></ptext>
  </para>
</root>