What is the difference between "être" and "avoir" in French?

"Être" and "Avoir" are both essential verbs but serve different purposes:

"Être" (to be):

• "Être" is used to express states of being, identity, or conditions.

• It is used in forming compound tenses with certain verbs of motion and intransitive verbs.

• It is also used in the passive voice to indicate the subject's state or condition.

• Examples: Je suis étudiant (I am a student), Elle est fatiguée (She is tired).

"Avoir" (to have):

• "Avoir" primarily indicates possession or ownership.

• It is used to form compound tenses, such as passé composé (present perfect), where it functions as an auxiliary verb alongside the past participle of the main verb.

• "Avoir" is also used to express age, physical sensations, and certain idiomatic expressions.

• Examples: J'ai un livre (I have a book), Il a dix ans (He is ten years old).