Comitia, maybe? That's plural of comitium. 'Commitia' isn't a Latin word.
The word "dicta" is a Latin plural. The singular is dictum.
A "Pilus" is the Latin for a hair, so following the Latin rules for plurals, the plural is "pili".
Tu (singular). Vos (plural).
Tu. (singular) Vos. (plural)
Habes. (singular) Habetis. (plural)
The word "data" is technically a plural noun. However, it is commonly used in both singular and plural contexts in modern English.
Natavisti (singular "you"); natavistis (plural "you").
Vale! (to singular) Valete! (to plural)
Tu (singular) Vos (plural)
Alumna is a Latin word. (It is the feminine form of alumnus, plural alumni).And the feminine Latin plural of alumna is alumnae.
Depending on whether the you is singular or plural: Curas (singular) Curatis (plural)
Both the singular and plural form of this word is "processus", it does not differ.