What is the first word that Ky teaches Cassia to write?

Cassia hurries to the top of the hill to talk with Ky. She shows him how she learned how to draw a letter "C,"and then she asks him to teach her another letter. He teases her, telling her that she could look at the letters on her scribe to learn how to write. She points out that they look different. He says that it's called cursive. He decides to teach her the letter "A." It's the next letter in her name. He tells her that she is learning her name because if that's all she ever learned, she will have still have something.