Regulate is a synonym of Govern. Govern is a type of Control. Control is the opposite of Resist. Resistance is derived from Resist. 
Complicated is a synonym of Complex. Complex is a synonym of Tough. Tough is related to Man. Man is a type of Work. 
Regulate <--Synonym--> Govern --IsA--> Control <--Antonym--> Resist <--DerivedFrom-- Resistance 
Complicated <--Synonym--> Complex <--Synonym--> Tough <--RelatedTo--> Man --IsA--> Work 