I can dive,” Sophia said. “Do you know what it feels like when you dive?”“Of course I do,” her grandmother said. “You let go of everything and get ready and just dive. You can feel the seaweed against your legs. It’s brown, and the water’s clear, lighter toward the top, with lots of bubbles. And you glide. You hold your breath and glide and turn and come up, let yourself rise and breathe out. And then you float. Just float.
-- Sophia (chapter 1)

Importance: This quote represents the freedom of the ocean. Sophia swims because she wants to live freely without the pain of losing her mother. When she dives, she is even more able to leave behind any conception of the feelings she must confront when she is back on land. She can float away.

From a passing rowboat it was obvious that each tree was stretching away from the...
-- Sophia (chapter 3)