Which beginning (prefix) or ending (suffix) can the following lists of words have in common? E.g. risk – wind – health: y Dress – do – happy – lucky

Вопрос школьника по предмету Английский язык

Which beginning (prefix) or ending (suffix) can the following lists of words have in common?
E.g. risk – wind – health: y

Dress – do – happy – lucky

Ответ учителя по предмету Английский язык

preffix un.

undress. undo. unhappy. unlucky.