From URL: \?option=com_content&view=article&id=1003:this-is-the-article&catid=52:this-is-the-category&itemid=78$
To URL: http://{siteurl}/secciones/this-is-the-category/1003this-is-the-article
Request only: true (checked)
Case sensitive: false (unchecked)

From URL: \?option=com_content&view=article&id[0-9]+:.*&catid=[0-9]+:.*&Itemid=[0-9]+$
To URL: http://{siteurl}/secciones/${cat}/${id}-${slug}
Request only: true (checked)
Placeholders:
cat={preg_match 1}/catid=[0-9]+:(.*)&Itemid=/{/preg_match}
id={preg_match 1}/id=([0-9]+):(.*)&catid=/{/preg_match}
slug={preg_match 2}/id=([0-9]+):(.*)&catid=/{/preg_match}

query={query}
cat={preg_placeholder 1,query}/catid=[0-9]+:(.*)&Itemid=/{/preg_placeholder}
id={preg_placeholder 1,query}/id=([0-9]+):(.*)&catid=/{/preg_placeholder}
slug={preg_placeholder 2,query}/id=([0-9]+):(.*)&catid=/{/preg_placeholder}