Matter
Item, Facts
noun
An action paragraph is a paragraph that shows the matter or the items or the facts. Sort of the action items, you know?
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
用紙に必要事項を記載のうえ、郵送をお願い致します。
Could you fill out the form and mail it to us, please?