学完隋朝的历史，你认为隋朝开凿的大运河，其主要作用是[ ]
A．加强北部边防
B．促进南北经济交流
C．巩固对南方的统治
D．方便隋炀帝南巡
答案：B
I know a lot about football. Now I want to learn _____ about it. [ ]
A. many
B. some
C. more
《雨巷》里“丁香姑娘”具有怎样的象征内涵？
