Mary is an eighteen-year-old with trade school education. She wears glasses and is a very artistic person. Mary is eighteen, which means she is a strong young adult and because of her education she will be very useful on the island. At trade school they teach their students a specific set of skills. The skills mostly regard working with hands.
That being said, Mary could help build living areas or help Dr. Dane with the digging and retrieving the plants to supply the other people with food. Also, she is artistic so she will think outside of the box. When people have trouble figuring different problems out on the island, she will provide a different solution that could benefit others.