staple of conversation的用法和樣例：
例句
- Football is his main topic of conversation.
足球是他的主要話題。 - At a private Australian Chamber of Commerce dinner held in Beijing on Wednesday night with former foreign minister Alexander Downer, Mr Hu was the main topic of conversation.
周三晚在北京和前外長唐納一起參加一家私人澳洲商會舉行的晚宴，胡士泰事件是主要話題。
