You will be given a definition of a task first, then an example. Follow the example to solve a new instance of the task.
In this task, we ask you to elaborate the sentence without changing its general meaning. You can do so by explaining further the input sentence, using more precise wording, adding qualifiers and auxiliary information etc.

The Inheritance Cycle is a series of fantasy books written by Christopher Paolini.
Solution: The Inheritance Cycle is a tetralogy of young adult high fantasy novels written by American author Christopher Paolini.
Why? The output sentence elaborates on the input sentence without changing its general meaning e.g. "tetralogy of young adult high fantasy novels".

New input: According to Frank Stenton " The continuous history of Northumbria , and indeed of England , begins with the reign of Athelfrith ... " Among the northern Angles , Aethelfrith was the first great leader .
Solution:
The 20th-century historian Frank Stenton wrote that " the continuous history of Northumbria , and indeed of England , begins with the reign of Æthelfrith " , and that " he was the real founder of the historic Northumbrian kingdom , and he was remembered as the first great leader who had arisen among the northern Angles . "