As Bob ran down the road. He fell over.

Because the thunder roared. The hobbits hid.

The goblins attacked. While Bilbo slept in a cave.

The cart came to a wheezing halt. Because Grandalf strode into the hobbit hole.

Jim rang his friend. Because he was interested in the idea.

Owls are nocturnal. Which means they are active at night. And they have excellent eye sight.