What is a sentenial in ambrose bierce's story

Explanation:

Esperanza is jealous of Alicia because she has a town to call home, Guadalajara, and she will return there someday. Alicia observes that Esperanza already has a home. But Esperanza shakes her head. She does not want to have lived in the house for a year, or to come from Mango Street. She declares that she will never come back to Mango Street until someone makes it better. Then Alicia asks who will make it better, suggesting the mayor as a possibility. The girls laugh because the idea of the mayor coming to Mango Street is so far outside the realm of possibility.