و، یا، اما

Add an item. کتاب و دفتر means “a book and a notebook.” Two coordinated words keep their own identities. In a list, و commonly comes before the final item rather than being repeated before every word.

Offer a choice. چای یا قهوه؟ asks “Tea or coffee?” Context determines whether the choice permits one option or more; یا alone is not a logic instruction about every possible situation.

Contrast clauses. من اینجا می‌مانم، اما سارا می‌رود means “I will stay here, but Sara will go.” Each clause has its own subject and verb form.

The linking و can be pronounced o in familiar spoken combinations. That sound is not automatically the reduced direct-object marker ـو. In کتاب و دفتر it connects two items; in کتابو خوندم the attached spoken object marker has another job.

Coordinating adjectives with و differs from placing them in a plain ezafe chain. Follow the complete phrase rather than inserting a connector between every adjacent adjective.