Answer:
She is surprised because he is a simple shepherd and shepherds do not usually know how to read.
Step-by-step explanation:
"The Alchemist" is a book written by Paulo Coelho. In this book, we get to know Santiago, who decides to travel the world while searching for answers to his own life. Santiago becomes a shepherd and in one of his trips he becomes friends with the daughter of a merchant, with whom he talks frequently. He tells her that he learned to read in his hometown, at a school and that surprises her, since it is not common for shepherds to read, since studying is something very elitist in this region.