And we only have a limited number of hydrogen bonds on the surface. So on the surface of the water, the water molecules are more restricted. That is because they cannot interact well with the air molecules above. And even the smallest rotational movement can cause them to lose those limited number of hydrogen bonds that they have in the first place. And because these water molecules remain in their location, they don't move, they stand their ground. When we apply a force, those molecules still don't want to move.