Rule reminder
The impersonal 'si' is used with a third-person verb when the subject is unspecified. With intransitive verbs or verbs followed by an infinitive, use the singular: Si parla italiano. With transitive verbs and a noun object, the verb agrees with the object: Si vendono case. With adjectives and 'essere', use the plural masculine: Si è stanchi.
In questo ristorante ________ molto bene.