Introduce is a type of Project. Introduce is related to Greet. Greet is a type of Address. Address is related to Book. 
Requirement is related to Rule. Rule is related to Restriction. Constraint is a type of Restriction. 
Project <--IsA-- Introduce <--RelatedTo--> Greet --IsA--> Address <--RelatedTo--> Book 
Requirement <--RelatedTo--> Rule <--RelatedTo--> Restriction <--IsA-- Constraint 