Scientists say it may be five or ten years it is possible to test this medicine on human p

发布时间：2020-08-17 12:43:17

Scientists say it may be five or ten years     it is possible to test this medicine on human patients.
A. since
B. before
C. after
D. when

网友回答

A. since
(答案→)B. before
C. after
D. when
解析：本题是考查连词的用法。本题的关键是理解句子的含义：“科学家说还需要五到十年才有可能将药物在人体身上进行实验。”只有B选项符合题意。
以上问题属网友观点，不代表本站立场，仅供参考！