school english speech contest的school后面是不是一定要加's

问题描述:

school english speech contest的school后面是不是一定要加's
如题,字典上school可以定语,那么这里是不是一定要加's
求有依据的解释

school 这里作为可以作为一个地点状语 也可以作为 定语
school's english speech contest 就一定要加
做状语 english speech contest in(at) school
整个名词 The English Speech contest of school