题目

I am happy to see great _________ have taken place in my hometown. Many new roads have been built.A.experiences B.changes C.dreams D.ideas 答案：【答案】B【解析】句意：我很高兴看到我的家乡发生了巨大的变化。新建了许多道路。考查名词辨析。experiences经历；changes变化；dreams梦想；ideas主意，根据Many new roads have been built. 新建了许多道路。可知家乡变化很大，故选B。某正数的平方根为a3和2a-93，则这个数为（　　）A．1B．2C．4D．9