Answer:
Il/Elle: Pronouns used as a singular usage of a male/female, often used to describe objects, singular person, or animal.
Example:
"Il est heureux" = "He is happy"
"Elle est fâchée" = "She is angry"
"Le liver" = The book
"La Pomme" = The apple
Ils/Elles: Pronouns used to refer to plural groups - 'Ils' is used for men, masculine nouns, or a mixed group of genders, whereas 'Elles' is used for a group of women/feminine nouns.
Example:
"Elles est parlent Français" = "They (group of girls) speak French"
"Ils rigolent" = "They (males/mixed genders) laugh"
On:
In special cases, 'On' may mean "you", "they", or people in general, and can often be an informal replacement for "we". It's always conjugated as a third-person singular.
Example:
"On va à la plage? " = "Shall we go to the beach?"
"On continue" = "Let’s move on"