How do gandalf and the eagle now each other?

These two characters now each other through prior engagments. the cheif eagle was wounded from an arrow shot by the humans and was almost dead when gandalf showed up and healed him and the eagle was in debt to the wizard gandalf.

Why would Bilbo name his sword "sting" after he killed the spider?

The reason that bilbo named his sword sting is because the spider had a stinger and Bilbo killed the spider, thus creating the name of sting.

Cory

Why do you think the dwarves like singing?

The dwarves love to sing because it motivates and determines them.

Why didn't Gandalf recount everybody after one of the Dwarves was taking by a goblin?

The only reason that Gandalf didn't take a head count was because it was very dark in the cave and they didn't have enough time to stop and pull everything together, they were getting chased and needed to escape quickly, so anyone left behind was by themselves.

What could the ring be used for?

This ring will make him invisible and this will allow him to get his friends back. But this ring only works when it is on your finger.

Is Thorin in any sense a heroic leader? Do his actions in the novel make him deserving of his death at the end?

Why are the goblins scared of the two swords?

They are scared of the swords because their ancestores have been slaughtered by these to swords and the head goblin was just killed and the lower goblins don't want to be killed but they got mad and chased the 13 dwarfs, the hobbit, and the wizard. when the goblins caught up they caught all of the dwarfs and the wizard but not the hobbit and then he found a ring.