第15题: [单项选择]Since 1970, millions of enthusiasts ______ a substance which they believe can remedy the common cold — Vitamin C. A. have taken B. have been taking C. have been taken D. have being taken 参考答案:B 答案解析:[解析] 由题干中的Since 1970可知,主句的时态应使用现在完成进行时,故答案为[B]。
第27题:[单选题]SGSN的下面哪些信息不需要通告给漫游合作伙伴?()
The following information of the SGSN does not need to be notified to the roaming partner: ( ). A.GT号码
GT number B.MCC+MNC C.GTPC地址
GTPC IP address D.GTPU地址
GTPU IP address 参考答案:A