Time for action – adding curves to the boat's lines by subdividing

You've discovered two of box-modeling's most powerful methods: extrusion and moving vertices. Now, it's time to discover the third one: subdividing. Now, the hull will begin to look like a boat after you perform the following steps:

1. Press A to deselect all vertices.
2. Select Edge Select mode on the 3D View header.
3. Press B to do a Border select to select the edges of the sides of the boat, but not the bow or the stern, as shown in the following image:
   
4. Press W to get the Specials menu. Select Subdivide with the LMB.
5. On the left, in the Tool Shelf, a subpanel is labeled Subdivide. Make sure that the arrow next to the word Subdivide is pointing down. Change Number of Cuts to 3. Blender will cut each of the edges into three as shown in the following image. Press A to deselect the edges. Now, you can see the new edges better.
   
6. Change to the Vertex Select mode in the 3D View header.
7. Select the vertices of the bow...