Helen has the habit of touching her fingertips to her lips and moving them like she feels the lips of others moving. Although she can imitate the motion made when a person talks, she emits no sound. According to Percy, when Helen does this, she is trying to talk.
Percy notes Helen's action twice in the play, and both times he says, "she tryin' talk." The first time this happens is in Act 1; Percy, Martha, and Helen are playing with paper dolls, when Helen begins poking her fingers inside Percy's mouth to feel his tongue. Annoyed, Percy tries to bite her fingers, and Helen jerks them away, placing them now on her own lips as she moves them in imitation of Percy's lips, but soundlessly. Percy tells Martha, "She tryin' talk. She gonna get mad. Looka her tryin' talk." Percy recognizes that Helen is aware that people communicate with their mouths, through speech, but, unable to replicate the process herself, she gets extremely frustrated.
The second time Percy notes that Helen is trying to talk is in Act 2, right after the Kellers have left, leaving Helen alone with Annie who is trying to establish her authority so that she can teach the child to communicate using signs. Helen is angry at being left with Annie, and refuses to interact with her, so Annie solicits the help of Percy. Percy does not want to get involved, but Annie is insistent, and when Helen realizes that Percy is there, she is elated and again puts her fingers into his mouth. She then, like before, puts her fingers to her own lips, trying once more to emulate what Percy does when he talks. Percy tells Annie, "She tryin' talk," and, knowing from past experience how frustrating this is for her, and how angry she gets, adds, "She gonna hit me."