Abstract
This study analyzes the OFROM corpus to set out a phenomenology of the passive oral diathesis. Taking a corpus analytical approach requires defining the structure in formal terms so that it can be searched with concordancing software. After searching the corpus for examples, several characteristic aspects of the oral use of the passive form are analyzed: the relationship with the active form, when it is linearized with the passive one; the correlation between the agent (par NP), the lexical aspect of the verb and the grammatical aspect of the verb tense; the aspectual values of the passive and their difficult use; the status of the voice auxiliary verb être and the progress of its grammaticalization in this function.