题目

When he was retired and went back home in _____, he was already in______.A. the fifties; his sixty              B. fifties; his sixtiesC. the fifties; his sixties            D. fifty; sixty 答案：C下列地理现象和太阳活动无关的A.高频无线电波突然衰减B.指南针不能正确指示方向C.最近几年全球各地气候异常D.火山喷发