The letter S is used in English for various purposes other than forming plurals. Here are some examples: Third person singular verb forms: The letter S is added to the base form of a verb to create the third person singular present tense. For example: "He walks to work every day." Possessives: The letter S is added to a noun to show possession. For example: "This is Sarah's book." Contractions: The letter S is used in some contractions, such as "it's" (it is), "he's" (he is), and "she's" (she is). Adjectives: The letter S is used to form adjectives from nouns, such as "watery" (water) or "woody" (wood). Adverbs: The letter S is used to form some adverbs from adjectives, such as "happily" (happy) or "quickly" (quick). Pluralizing nouns that end in -s, -z, -x, -sh, or -ch: When a noun ends in one of these sounds, the letter -es is added to make the plural. For example: "boxes" (box), "watches" (watch), "buses" (bus). Forming possessive nouns that end in -s: To show possession of a singular noun that ends in -s, you can add an apostrophe followed by an -s. For example: "James's car." Making abbreviations or acronyms plural: When an abbreviation or acronym includes the letter S, you can add an apostrophe followed by an -s to make it plural. For example: "The CEO attended several CFOs' meetings."

Also a possessive "s". Usually has an apostrophe. (Name)'s - Ahmed's question about grammar is interesting. (object)'s - The doll's head is spiky.

Per coniugare il verbo alla terza persona: he, she, it