Examples of Foreign Nouns and Their Plural Forms:
Latin:
* Singular: alumnus (male graduate) / alumna (female graduate)
* Plural: alumni (male and female graduates)
* Singular: curriculum (course of study)
* Plural: curricula (courses of study)
* Singular: datum (piece of information)
* Plural: data (pieces of information)
Greek:
* Singular: criterion (standard of judgment)
* Plural: criteria (standards of judgment)
* Singular: phenomenon (observable fact)
* Plural: phenomena (observable facts)
* Singular: octopus (eight-armed sea creature)
* Plural: octopuses or octopi (both are accepted, though "octopuses" is more common)
French:
* Singular: beau (handsome man)
* Plural: beaux (handsome men)
* Singular: bureau (desk)
* Plural: bureaux or bureaus (both are acceptable)
Italian:
* Singular: bambino (baby boy)
* Plural: bambini (baby boys)
* Singular: soprano (high-pitched voice)
* Plural: soprani (high-pitched voices)
German:
* Singular: kindergarten (pre-school)
* Plural: kindergartens (pre-schools)
* Singular: zeitgeist (spirit of the times)
* Plural: zeitgeists (spirits of the times)
Note: Some foreign nouns have become so integrated into English that they have adopted the regular English plural form (e.g., "octopus" - "octopuses"). Others still maintain their original plural forms.