题目内容 (请给出正确答案) [主观题] According to the passage, when could people start using a maglev commerciaily?A.In 5 years . B.In 10 years.C.In 20 years.D.In more than 20 years. 查看答案 如搜索结果不匹配,请 联系老师 获取答案