Scientists say it may be one year or so ________ it is possible to test the new medicine on human pa...
2023-01-13 05:32:20 123次 2011-2012学年浙江省高三上学期期中考试英语题 单项填空 反馈错误 加入收藏 正确率 : 100%
题目内容：
Scientists
say it may be one year or so ________ it is possible to test the new medicine
on human patients.
A. when B.
after C.
before D. since
本题链接：
