单项选择题

How many more decades will have to pass_____scientists succeed in providing a cure for cancer？

A．when
B．before
C．since
D．until
<上一题 目录 下一题>
热门 试题

单项选择题
There is so much work _____today Would you be kind enough to lend me a hand？
A．having done
B．to be done
C．being done
D．will be done
单项选择题
He changed his name， _____ that nobody would find out what he had done before.
A．having thought
B．to think
C．thinks
D．thinking
相关试题