The question is basically asking how characters in the play act in a different way than society would expect them to act. In this case, it is really asking about women and how they are behaving in a way that would have shocked society in their day. Remember, we are talking about a very long time ago. What Moliere does is show us one character that does act as society would expect (Mariane) and then shows a contrast with other female characters, such as Elmire and Dorine.
Mariane is the perfect young woman of the time. She is very obedient to her parents; in fact, when her father tells her she has to give up the fiancé she loves in order to marry the man of his choice, she does not argue with him. She is upset, but even so, when Dorine suggests she argue with her father, she is shocked and tells her she could never do that. In the end, she marries the man she loves, but only because others in the play intervened.
Elmire is a good example of a woman who does not act as her gender should in the play. In her marriage to Orgon, it is clear that Elmire is in charge. This may even be why Tartuffe ends up in the house in the first place—Orgon is trying to assert his authority that was lost long ago.
Dorine is also an excellent example of a woman who does not “know her place.” Dorine talks back, not only to her bosses, but to everyone around her. As our perfect example of a woman is Mariane, it is obvious that Dorine is not acting like the other girls of her day. When she should close her mouth, she opens it. When she should not argue, she argues. An example of this is when she is trying to explain to Orgon that he should not marry Mariane to Tartuffe, and she tells him, proudly, that she would never let a man choose who she married.
In short, Mariane is the best example of the girl of the day—sweet and obedient. The other two women are representing girls in that society who are trying to break free.