Proposal is a type of Message. Introduction is a type of Proposal. Introduction is a type of Textbook. 
Flag is related to Day. Day is related to Bright. Bright is related to Ribbon. you are likely to find Ribbon in/at/on Bath. 
Message <--IsA-- Proposal <--IsA-- Introduction --IsA--> Textbook 
Flag <--RelatedTo--> Day <--RelatedTo--> Bright <--RelatedTo--> Ribbon --AtLocation--> Bath 