Question

after all

at all 和after all都有到底的意思,那它们有什么区别呢?
比如She said she would not go to the palace ball,but she went there after all.
He is very lazy,but he passed the exam at all.
I was tired and walked more slowly,but went home at all.这里用after all 好像也行呀?真是很难区别,
at all有最终，到底的意思！

Answer 1

这两个词组意思不太一样
after all 毕竟,到底（这个到底指“最终还是”,有出乎意料的意味）,一般用在肯定句中
如：Don't blame him,after all he is only a child.别责备他,他毕竟只是个孩子啊.
楼主的后两个例句也应该用after all.
He is very lazy,but he passed the exam after all.他很懒,但还是考及格了.
I was tired and walked more slowly,but went home after all.我很累走得慢,但最终还是到家了.
at all 根本（不）,一点儿（也不）,用在否定句中居多
如：I don't know him at all.我根本不认识他.
It doesn't matter at all.一点儿也没关系.
答楼主补充问题
at all 意思为“到底”时一般用在疑问句中：
Do you know this place at all?你到底了不了解这里?
这里的“到底”与after all那个“到底”的意思不同.
at all作“到底”讲时,是“有没有哪怕是一点儿?”
after all作“到底”讲时,是“终于还是”.