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：本题考查动词短语辨析。turn sth.over in one’s mind的意思是“仔细考虑或反复思考某事物”。
