题目内容
Doctors say it will be many years ___________ scientists develop an effective treatment for AIDS.
A. when B. since C. before D. as
C
考查时间状语从句的连词。 题意:医生说要找到一种有效的治疗艾滋病的方法还需要很多年。
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题目内容
Doctors say it will be many years ___________ scientists develop an effective treatment for AIDS.
A. when B. since C. before D. as
C
考查时间状语从句的连词。 题意:医生说要找到一种有效的治疗艾滋病的方法还需要很多年。