He the problem in his mind for a whole week before he did anything about it.A. switched; o

问题补充：

He the problem in his mind for a whole week before he did anything about it.

A. switched; on

B. kicked; up

C. turned; over

D. took; on

答案：

A. switched; on

B. kicked; up

(答案→)C. turned; over

D. took; on

解析：句意：在采取措施之前，他在脑中将这个问题反复思考了一个星期。turn over :to think about carefully仔细考虑；switch on把开关打开；kick up引起；take on呈现、雇用、承担。