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

中国抗日战争取得胜利的根本原因是( )。

A．国共实现了二次合作

B．国际反法西斯同盟的支援

C．实现了全民族抗战

D．中国军队的英勇作战