Harvest is the opposite of Plant. Plant is the opposite of Seed. Seed is a type of Object. Object is related to Cake. 
Water is a type of Fill. Water can Wet. 
Harvest <--Antonym--> Plant <--Antonym--> Seed --IsA--> Object <--RelatedTo--> Cake 
Fill <--IsA-- Water --CapableOf--> Wet 