Question

---_______do you have an art festival in your school?
---Once a year.

A．How long	B．How often
C．How far	D．How soon

Answer 1

B

解析试题分析：句意:你们学校多久举行一次艺术节？一年一次。A. How long多长时间，B. How often多久一次，C. How far多远，D. How soon多快。给表示频率的词组Once a year.提问要用how often，据句意，故选B。   
考点：考查疑问词。