there are ____ more people in Hebei than in Yancheng

选择many
many more后接一个名词一定是个复数可数名词.若不接名词,则more本身就被看作是一个复数名词,表示复数概念.如：
Some students are against the plan,but many more support it.一些同学反对这项计划,但是有更多人支持它.
We have many more left.我们还剩下很多.
much more后接一个名词,这个名词一定是个不可数名词.若不接名词,则more本身就被看作是一个不可数名词.如：
The farmers have produced much more rice.这些农夫收了更多的稻谷.
She has much more to do.她还有很多事要去做.