膳食调查报告的标题应该反映调查的（）等信息。
A.地点
B.人群性质
C.内容
D.作者
E.结论
参考答案：A, B, C
He tried his best to solve the problem , ______difficult it was. [ ]
A. however
B. no matter
C. whatever
D. Although
女士规范站姿是什么？
