The government has taken some measures to solve the shortage of electricity , but it may be some time the situation improves.
A. since
B. when
C. before
D. unless
网友回答
A. since
B. when
(答案→)C. before
D. unless
解析：考查固定句型。It be 一段时间before 从句，表示一段时间以后某事才发生。Before时间状语从句里用一般现在时表示将来时，主句里可以使用将来时或者情态动词。句意：也许一段时间以后情况才会改善。