You use hers to indicate that something belongs or relates to a woman, girl, or female animal.
His hand as it shook hers was warm and firm.
当他握住她的手时,他的手温暖而有力。
Professor Camm was a great friend of hers.
卡姆教授是她的一位挚友。
In written English, hers is sometimes used to refer to a person without saying whether that person is a man or a woman. Some people dislike this use and prefer to use 'his or hers' or 'theirs'.
The author can report other people's results which more or less agree with hers.
作者可以报道与自己的观点或多或少一致的别人的成果。