Original sentence: While "countries" is the term commonly used to describe them, because of a lack of a formal British constitution, and owing to a convoluted history of the formation of the United Kingdom, a variety of other terms are also used
Edited sentence: While "countries" is the term commonly used to describe them, because of a lack of a formal British constitution, and owing to a convoluted history of the formation of the United Kingdom, no official appellation exists and so various terms are used