The Latin plural of the noun apparatus is actually apparatus (the vowel lengthens, but that's not reflected in the spelling). The English plural is apparatuses. You don't actually hear the English plural apparatuses that often, because apparatus is treated as a semi-uncountable noun: one apparatus, two pieces of apparatus. "Apparati" is incorrect in either language.
The plural form of apparatus is apparatuses. It has no foreign plural.
The plural form of plastic is plastics.
The plural form of building is buildings.
The plural form for the noun 'material' is materials.
The plural form is technologies.
The plural form of apparatus is apparatuses. It has no foreign plural.
The foreign plural form of symposium is symposia, while the English plural form is symposiums.
The plural form of addendum is addenda
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 "adiós," and in Italian it would be "addii."
Forum---Plural Form Forums,Foreign Plural Form Forumina
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."
The English plural form of "bacterium" is "bacteria."
The English plural form of "syllabus" is "syllabi."
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.
The noun 'apparatus' is an uncountable noun, it has no plural form.The noun 'apparatus' is a type of aggregate noun, a word representing an indefinite number of elements or parts.
Ova is the plural form. The singular form is ovum.