Subject question: Whom haven't we seen for ages?
Yes/no question: Haven't we seen him for ages?
Alternative question: Haven't we seen him or her for ages?
Tag question: We haven't seen him for ages, have we?
Special question: For how long haven't we seen him?
Subject question: Whom haven't we seen for ages?
Yes/no question: Haven't we seen him for ages?
Alternative question: Haven't we seen him or her for ages?
Tag question: We haven't seen him for ages, have we?
Special question: For how long haven't we seen him?