You will be given a definition of a task first, then some input of the task.
You will be given a context, a subject and a relation. Your task is to generate a question based on the subject and relation. The generated question should include the given subject. Try to use a minimum number of words that are not present in either context, subject or relation while generating question.

Context : The editor felt that something was missing between third and fourth volumes, so Taran Wanderer was written one month after The Castle of Llyr was published.
Subject : Taran Wanderer
Relation : series
Output:
What series is Taran Wanderer a part of?