The plural for for the noun celebrity is celebrities.
The plural possessive form is celebrities'.
example: An army of photographers were on hand for the celebrities' arrivals.
The plural possessive form of actress is actresses'.
The possessive form of the plural noun actress is actresses'.
The possessive form of the plural noun sopranos is sopranos'.Example: The sopranos' rehearsal is scheduled for two.
There is no singular possessive of "actresses". The word itself is plural. The singular possessive of actress, however is "actress's."
The possessive singular of all English nouns is formed by adding-'s: actress's. The use of an apostrophe alone is reserved for PLURAL possessives.
Singular possessive: secretary's Plural: secretaries Plural possessive: secretaries'
The plural is lads. The plural possessive is lads'.
The plural is relatives. The plural possessive is relatives'.
The plural form is suffixes. The plural possessive is suffixes'.
The plural form is stepsisters. The plural possessive is stepsisters'.
The plural form is Mexicans. The plural possessive is Mexicans'.
The plural form is echoes. The plural possessive is echoes'.
The plural form is inches. The plural possessive is inches'.
Studies' is the plural possessive of study.
The plural possessive is pals'.
Coaster's is singular possessive. The plural is coasters, the plural possessive is coasters'.
The plural possessive of bandit is bandits'.