you are likely to find Ticket in/at/on Pocket. Ticket is related to Fare. 
Condition is a type of Illness. you are likely to find Illness in/at/on Brain. Brain is part of Body. 
Pocket <--AtLocation-- Ticket <--RelatedTo--> Fare 
Condition --IsA--> Illness --AtLocation--> Brain --PartOf--> Body 