after-school 是合成形容词可以修饰名词，它不是副词，表示“课后，课外的”的意思。

副词。

after school是时间副词短语

after school什么意思?

after school：放学后
例如：
I took the kids for a picnic in the park after school.
放学后我带孩子们去公园野餐。

意思是放学了