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 is technologies.
The plural form for the noun 'material' is materials.
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 singular form is bacterium; the plural form is bacteria.
The plural of syllabus is syllabi.
the word emphasis is already singular because when in foreign plural it is emphases
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.
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.