Professor James will give us a lecture on the Western culture, but when and where yet.
A. hasn’t been decided
B. haven’t decided
C. isn’t being decided
D. aren’t decided
网友回答
(答案→)A. hasn’t been decided
B. haven’t decided
C. isn’t being decided
D. aren’t decided
解析：根据句意，此处应用被动语态，不用主动语态; 再根据句末的yet可知，最好用现在完成时。故选A最佳。