A libretto may undergo an adaptation.Logical formLearned from4 sentences. A libretto may be based on a male.Logical formLearned from3 sentences. A libretto can be modified.Logical formLearned from3 sentences. A male can be an author of a libretto.Logical formLearned from3 sentences. A libretto may undergo an edition.Logical formLearned from3 sentences. Librettos can be for some operas.Logical formLearned from3 sentences. A libretto may be based on a novel.Logical formLearned from3 sentences. A composer can be to a libretto.Logical formLearned from3 sentences. An opera may use a revised version of some libretto.Logical formLearned from3 sentences. A revised version can be constituted-of-or-filled-with some libretto.Logical formLearned from3 sentences. Some acts can be with libretto.Logical formLearned from3 sentences. A libretto may be based on a short story.Logical formLearned from3 sentences. A libretto can be for a production.Logical formLearned from3 sentences. Libretto can be in a language.Logical formLearned from3 sentences. A style may pertain-to a libretto.Logical formLearned from3 sentences.