19.-20.What two agents
Or natural forces
cause this rock formation to look like this?

-1

Explanation:

20-19=-1

The idea of twilight being a calm time, as the title suggests, is present many times throughout the poem. The very first line of the poem uses the word "pleasant" to describe this time of day, beginning with the idea of a nice, calm evening. The speaker describes the animals being done with their work, and many animals "sitting" or "settling" for the evening. All of these words give the reader an image of a day winding down and calming down at twilight.