The policeman came up to see what was the matter.这句话对吗

问题描述:

The policeman came up to see what was the matter.这句话对吗
我主要是不清楚what was the matter在从句中不是应该将was 放到后面去吗

因为在这里the matter相当于wrong,是一个形容词,而形容词是不能做主语的,故此只能保持原语序,由what充当连接词和主语