Style, comments, small improvements

Nope :)

> Some people, especially those who are trying extra hard to sound erudite, will use “an” before a word that begins with the letter “h,” such as “an historical artifact.” In the United States, this usage is incorrect. Instead, we write, “a historical artifact.”

Source: http://www.englishrules.com/writing/2005/a-versus-an-the-indefinite-article/

Example:
> Because it is so brief, a haiku is necessarily imagistic