—MrHu,canyoutellushowtolearnmathwell?      —Sure.Butre...

问题详情：

 —Mr Hu, can you tell us how to learn math well?

       —Sure. But remember nothing can be learned _________ hard work.

     A. by          B. at            C. without       D. for

【回答】

C 

知识点：介词和介词短语

题型：选择题