A-A+
How many more decades will have to pass ______
问题详情
How many more decades will have to pass ______ scientists succeed in providing a cure for cancer？
A．when
B．before
C．since
D．until请帮忙给出正确答案和分析，谢谢！
参考答案
正确答案：B
解析：本题考查的是固定句式。when当……时候；before在……之前；since自从；until直到。还要有多少年过去之后，科学家才能够成功地发现治疗癌症的方法?
