就是构词法不同而已,school-age是名词组合成的,上学年龄
而middle-aged是更加常见的构成方式,即adj.+名词-ed
warm-hearted
black-haired
yellow-skinned
bright-colored
blue-eyed
就是构词法不同而已,school-age是名词组合成的,上学年龄
而middle-aged是更加常见的构成方式,即adj.+名词-ed
warm-hearted
black-haired
yellow-skinned
bright-colored
blue-eyed