为什么go to school（去上学）要加"to",而go swimming中间却不加"to"?

为什么go to school（去上学）要加"to",而go swimming中间却不加"to"? 去购物的英语是go shopping 而去上学的英语是go to school 为什么两者都是去.而一个要加to呢? 为什么不是GO TO SWIMMING而GO TO SCHOOL\VISIT TO ENFLAND? 为什么上学不说go to the school,而说go to school go to school是上学还是去上学? 为什么go to school不用加the? 去上学用英语怎么说,除了go to school. 英语中为什么用go swimming,而不用go to swimming? 看到这样的解答 go to the school是去学校的意思,而go to school是去上学 在国外他们真的有这种 She will____(go)swimming this afternoon.tom___(go)to school go to school为什么要加to?它的同义短语是什么?可不可以是go to the school? 去学校是go to school 而 去公园就是go to the park