English undergo

← Old English undergān (inherited)

← German untergehen (cognate)

← English under (prefix)

← English go (prefix)

← Middle English undergon (inherited)

← Dutch ondergaan (cognate)

← Swedish undergå (cognate)

→ English undergoer (suffix)

→ English undergoeth (suffix)

→ English undergoest (suffix)

→ English reundergo (prefix)