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: It is usually painted on both sides of the aircraft , most often in the tail area , although in some cases the serial is painted on the side of the aircraft 's fin / rudder ( s ) .
Solution:
In air forces , the serial number is used to uniquely identify individual aircraft and is usually painted on both sides of the aircraft fuselage , most often in the tail area , although in some cases the serial is painted on the side of the aircraft 's fin / rudder ( s ) .