S-row irregular conjugation: an irregular conjugation class with an s-stem. In modern Japanese, the verb "suru" (to do) and its compounds (e.g. benkyou-suru) are typical examples.
『する』はサ行変格活用なので、『する』の活用は他の五段動詞と異なる。
"Suru" is an s-row irregular conjugation, so its conjugation differs from other five-row verbs.
ビジネス文書でも『確認する』のようにサ変動詞はよく使われる。
Even in business documents, s-irregular verbs like "kakunin-suru" (to confirm) are often used.
文法問題ではサ行変格活用の活用形を答える問題が出ることがある。
Grammar exercises sometimes ask you to provide the conjugated forms of s-row irregular verbs.