Never stand up you are asked to.A. ifB. sinceC. unlessD. when

问题补充：

Never stand up you are asked to.

A. if

B. since

C. unless

D. when

答案：

A. if

B. since

(答案→)C. unless

D. when

解析：连词词义辨析题。A. if 如果 B. since 自从…以来 C. unless除非 D. when 当…时候“除非叫你否则不要站起来”