Hi, 
1. I encounter a strange problem regarding to spelling in my emacs. When I do spell-check-buffer(from menu), it will miss some mis-spelled words. But if I apply spell-check word to the same mis-spelled word, it can detect the mis-spelling. What could be the problem? 

2. What is the path of the private dictionary of ispell used by emacs? I want to delete some words which were inserted in  my private dictionary (by i in the speck check mode). 

Thanks.