根据句意，用所给单词的适当形式填空。
【小题1】He listed a few _________ (reason) why he was not interested in the project.
【小题2】The more I think about it, the _________ (angry) I get.
【小题3】And if I say the _________ (true), why do you not believe me?
【小题4】He liked to share his _________ (knowledge) not by answering questions but by asking them.
【小题5】You'll have to stay in after school if you still _________ (fail) to pass the examination.