Task: Question Generation
Input (English): Context : The Dark Hills Divide (Book 1) Beyond the Valley of Thorns (Book 2) The Tenth City (Book 3) Into the Mist (Prequel) Stargazer (Patrick Carman) (Book 4) 
Subject : The Dark Hills Divide 
Relation : series
Output (English): Which series is The Dark Hills Divide a part of?