第1题: [单项选择]What does the man say about the video game A. It involves learning geography. B. It is currently out of stock. C. It used to be very popular. D. It is the most expensive option. 参考答案:A
第17题: [填空题]S2 参考答案:is或
chemical∧is—which/that 答案解析:[解析] 若去掉is,则taken by drug addicts为过去分词短语做后置定语修饰medicine和chemical;若is前加that或which,则是that或which引导定语从句。