never before have so many people in our country been interested in sports为什么用have ,不用has

never before have so many people in our country been interested in sports为什么用have ,不用has
never before have so many people in our country been interested in sports
为什么用have ,不用has

never before have so many people in our country been interested in sports为什么用have ,不用has
这是Never引导的倒装句,主语是so many people,所以如此.