[正] He is a friend of my father\'s.
注:名詞前面的屬格,可代定冠詞用,如 my brother\'s wife=the wife of my brother. 又 my brother\'s friends=(all) the friends of my brother. 如果不是指某一個特定的人或幾個人時,則須用不定冠詞 (a),那是不能用屬格來代替的,即是用了屬格,還得有不定冠詞,但我們又不能說 my brother\'s a friend. 或 a my brother\'s friend,所以只好說 a friend of my brother\'s. 這種表現(xiàn)法所含有的意味是 a friend (that is) my brother\'s 或 one of my brother\'s friends. 這便是英語的雙重屬格的由來。