in French, singular 'un adieu', plural 'les adieux'
The English plural form of "adieu" is "adieux." The foreign plural forms can vary by language, for example in French it would be "adieux," in Spanish it would be "adiรณs," and in Italian it would be "addii."
The foreign plural form of symposium is symposia, while the English plural form is symposiums.
Forum---Plural Form Forums,Foreign Plural Form Forumina
The foreign singular form of "emphasis" is usually "emphases" in English, but it depends on the language. For example, in French, it is "emphase."
The English plural form of "syllabus" is "syllabi."
The foreign plural of "genius" is "genii" or "geniuses," depending on the context. "Genii" is the Latin plural form, while "geniuses" is the commonly used English plural form for the word "genius."
The foreign plural form of symposium is symposia, while the English plural form is symposiums.
The plural form of addendum is addenda
Forum---Plural Form Forums,Foreign Plural Form Forumina
The plural form of apparatus is apparatuses. It has no foreign plural.
data IS the plural form of datum.
The foreign singular form of "emphasis" is usually "emphases" in English, but it depends on the language. For example, in French, it is "emphase."
There are several possible plural forms of the English word cherub, which is a word of Hebrew origin. The one I think you are referring to is cherubim, which is derived directly from the Hebrew plural. Cherubs and cherubims also occur in English.
Ova is the plural form. The singular form is ovum.
Librettos
octopi
English
There are several plural forms of the word octopus: Octopuses is the most often used form cited in references in the US, but other forms are accepted such as octopi and octopodes.