归纳
参考答案：
以数据为基础，把数据反映的实际关系组织为理论原则。
.
If you compare food costs today ______ of a year ago, you will find the difference.
A．to that
B．to them
C．with that
D．with those
与甘草相反的药物是（）
A.半夏
B.贝母
C.瓜蒌
D.藜芦
E.海藻
