-----What do you think of concert last night? ---No doubt it was great success.A. a ; the

问题补充：

-----What do you think of concert last night?

---No doubt it was great success.

A. a ; the

B. the ; a

C. the ; 不填

D. a; 不填

答案：

A. a ; the

(答案→)B. the ; a

C. the ; 不填

D. a; 不填

解析：考查冠词。句意：你认为昨晚的音乐会怎么样？无疑它是个巨大的成功。结合语境可知上文特指昨晚的音乐会，故用定冠词。下文泛指任何一个成功，故用不定冠词。选B。