We usually have sports after class中的after为什么不能换成of

We usually have sports after class中的after为什么不能换成of after class,they usually have a rest After class,we have different kinds of _____(activity). After dinner,we usually have a walk -------- ---------- ---- three,usually,class,after,we,hours,soccer,for,have英语连词成句 We have fun ( )[speak] English after class after class they have lots of (s. We usually play football,（）and（）after class. we often have sports after school (改一般疑问句) After dinner ,we usually have some ( ) like ice cream 填空 We usually eat fruit after _____ （have） lunch We will have a ___ after class.(discuss)