是can both/all还是both/all can?

是can both/all还是both/all can? 是 are both还是both are of these,是用all还是both?为什么?怎么区别? 是ALL ARE 还是ARE ALL?是BOTH ARE 还是ARE BOTH?这两个用法不是很清楚. 英语问题求大神讲解!比如像both,also 之类的词 如果和can 这样的情态动词连用 是 both can 还是can both? Both of these are interesting books.You can borrow_____of them填any还是all 为什么 both of you前面加什么级?both of you前面是加比较级还是原级?例题：I can both of you.提示语是see/well both are还是are both Who can speak Japanese?We both (all) can. “两个都”是both are还是are both? both of us 主语是both 还是us? 是THEY ARE BOTH 还是THEY BOTH ARE 是both is ok 还是is both ok 是both ok还是both are ok?tell me why? both 后面是加名单还是名复?both of 是both ok还是both are ok?为什么? both both