What is one of the key features of blank verse?

The main characteristic of the blank verse is the absence of rhymes.

Explanation:

In the theory of literature, the White Verses, also called "Loose Verses" are those that do not present rhyme schemes, however they can present metrics (measure). White verses have been widely used since the 18th century, especially in romantic, modern and contemporary poetry.

the answer is somber

comfort   in their suffering