The term "be allowed to" is used to say that someone has the permission to do something. In a sentence make sure to change "be" to fit the subject (person).
For example: She is allowed to stay at her friend's house. OR They are allowed to use their Mum's computer.
For questions: Put "be" at the beginning of the sentence. For example: Are you allowed to come?
Negations: I am not allowed to watch that movie.