Bob ran down the road.
He fell over.

Bob fell over before he ran down the road.

The thunder roared.
The hobbits hid.

The hobbits hid because the thunder roared.

Bilbo slept in a cave.
The goblins attacked.

The goblins attacked because Bilbo slept in a cave.

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

Gandalf went into the hobbit hole after a cart came to a wheezing halt.

Jim was interested in the idea.
He rang his friend.

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

Owls are nocturnal.
This means they are active at night.
They have excellent eyesight.

Owls have excellent eyesight so that means there active at night because of that they are nocturnal.