expression
if this is not the case; otherwise; if not
Fixed conditional expression used to present an alternative or exception. Often appears in formal or written contexts.
そうでない場合は、別の方法を考えましょう。
If that is not the case, let's think of another way.
この書類に問題がなければそのまま提出してください。そうでない場合は、修正が必要です。
If there are no problems with this document, please submit it as is. Otherwise, corrections are needed.