French is a different concept from Impossible. Impossible is related to Difficult. 
you are likely to find Coin in/at/on Casino. you are likely to find Surveillance in/at/on Casino. Surveillance is derived from Survey. 
French <--DistinctFrom--> Impossible <--RelatedTo--> Difficult 
Coin --AtLocation--> Casino <--AtLocation-- Surveillance --DerivedFrom--> Survey 