Trunk is related to Wood. Wood is related to Starter. Starter is related to Seed. Seed is the opposite of Tree. 
Boast is related to Lie. Guilt would make you want to Lie. Guilt is related to Conscience. 
Trunk <--RelatedTo--> Wood <--RelatedTo--> Starter <--RelatedTo--> Seed <--Antonym--> Tree 
Boast <--RelatedTo--> Lie <--CausesDesire-- Guilt <--RelatedTo--> Conscience 