21 （2011·辽宁抚顺六校联合体高三一模） If China’s space technology has achieved ____ breakthrough in this field, it really is ____ amazing wonder.
A. the; an B. a; an C. 不填; the D. a; 不填
22（2011·浙江杭州七校联考） Straight away I went to buy the tickets, but there were _____ left for the next public holiday.
A. nothing B. none C. neither D. no one
