单项选择题
A. 广告的目的是吸引顾客,但它不强迫他们购买产品。 B. 广告不是逼迫顾客。而是吸引顾客购买产品。 C. 广告的目的是不强迫顾客购买产品,恳求顾客光顾。 D. 广告意在吸引顾客,而不是强迫顾客。
A. needn't have done B. must not have done C. should not have done D. can not have done
A. were B. had been C. was D. have been