Millie does everything _____(careful).She often leaves her books at home.为什么,我买的题的答案给的是uncarefully为什么这道题用uncarefully而不用carefuless?而且修饰不定代词的不是形容词吗?uncarefully是副词呀,怎么可以修饰everything呢?是careless不是carefuless

Millie does everything _____(careful).She often leaves her books at home.
为什么,我买的题的答案给的是uncarefully
为什么这道题用uncarefully而不用carefuless?而且修饰不定代词的不是形容词吗?uncarefully是副词呀,怎么可以修饰everything呢?
是careless不是carefuless