The possessive form for the mass noun gas is gas's.
Example: The gas's price has gone up again.
Gas’s
The possessive form for the noun substance is substance's.Example: The substance's origin could not be determined.
Synthesis is the singular form, syntheses is the plural form, and syntheses' is the plural possessive form.
The plural form of the noun laboratory is laboratories.The plural possessive form is laboratories'.
The plural form of the noun synthesis is syntheses.The plural possessive form is syntheses'.
The possessive form for the noun oxygen is oxygen's.
The singular possessive form is word's, for example the word's definition.
possessive form of the word glass: glass'
possessive form of the word Congress: Congress'
possessive form for the word holders: holders'
possessive form of the word Cathi: Cathi's
The possessive form of the word fairy is fairy's.
The possessive form of the word dictionary is dictionary's.
the possessive form of the word Cathie: Cathie's
The possessive form is Lindbergh's.
The possessive form is weaver's.
The possessive form for the interrogative pronoun who is whose.
The possessive form for the word 'word' is word's.