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—This returned scholar has become one of the top experts in this field.
—Yes, I know him very well. He ______ for ten years at an institute in the USA.
A. has worked B. has been working C. worked D. had worked
查看习题详情和答案>>—This returned scholar has become one of the top experts in this field.
—Yes, I know him very well. He ______ for ten years at an institute in the USA.
A. has worked B. had worked C. worked D. has been working
查看习题详情和答案>>―This returned scholar has become one of the top experts in this field.
―Yes, I know him very well. He ______ for ten years at an institute in the
A. has worked B. has been working C. worked D. had worked
查看习题详情和答案>>