In French, 'leur' is a pronoun that means 'their' or 'them' when referring to a group of people or things. It is used to indicate possession or indirect object. On the other hand, 'lui' is a pronoun that means 'him' or 'her' when referring to a singular person. It is used to indicate possession or as an indirect object. **

"Eux" and "leur" are both pronouns used in French to refer to people or things. "Eux" is used as a direct object pronoun to replace a group of people or things, while "leur" is used as an indirect object pronoun to replace a group of people. For example, "Je les ai vus" (I saw them) uses "les" as a direct object pronoun, while "Je leur ai parlé" (I spoke to them) uses "leur" as an indirect object pronoun. **

The object pronouns lui and leur are used to replace indirect objects in French. Lui is used to replace singular indirect objects, while leur is used to replace plural indirect objects. These pronouns come before the verb in a sentence and agree in gender and number with the noun they are replacing. For example, "Je lui parle" means "I am talking to him/her" and "Je leur donne des cadeaux" means "I am giving them gifts." **

Ses, leur, and leurs are all possessive adjectives in French, but they are used in different contexts. "Ses" is used to indicate possession by a singular third person, "leur" is used for a singular third person, and "leurs" is used for plural third person. For example, "ses chaussures" means "his/her shoes," "leur maison" means "their house," and "leurs voitures" means "their cars." It's important to pay attention to the number and gender of the noun being possessed in order to choose the correct possessive adjective. **

In French, "lui" and "leur" are both used as indirect object pronouns to replace nouns that are the recipients of the action. "Lui" is used to refer to a singular masculine or feminine noun, while "leur" is used to refer to a plural noun. For example, "Je lui ai donné le livre" means "I gave him/her the book," and "Je leur ai donné les livres" means "I gave them the books." It's important to remember that these pronouns must agree in gender and number with the noun they are replacing. **

You use "leur" when you want to indicate possession or belonging for a singular noun, and "leurs" when you want to indicate possession or belonging for plural nouns. For example, "leur maison" means "their house" (singular), and "leurs voitures" means "their cars" (plural). **

One can recognize when to use "leur" or "eux" by understanding their different functions in a sentence. "Leur" is a pronoun used to indicate possession or indirect object, while "eux" is a pronoun used as a subject or direct object. Therefore, if the pronoun is referring to possession or an indirect object, "leur" should be used. If the pronoun is referring to a subject or direct object, "eux" should be used. **

In French, "leur" is used as a singular possessive pronoun meaning "their" when referring to one person or thing. On the other hand, "leurs" is the plural form of "leur" and is used when referring to multiple people or things. So, the main difference between "leur" and "leurs" is that "leur" is singular and "leurs" is plural. **