Task: Question Generation
Input (English): Carnival has been celebrated for centuries. The tradition was likely established under Venetian rule around the 16th century. It may have been influenced by Greek traditions, such as festivities for deities such as Dionysus. The celebration originally involved dressing in costumes and holding masked balls or visiting friends. In the twentieth century it became an organized event held during the 10 days preceding Lent (according to the Greek Orthodox calendar). The festival is celebrated almost exclusively in the city of Limassol.
Output (English): How long has Carnival been celebrated?