Spit is related to Mouth. Mouth is related to Bite. 
Wood is related to Stair. Stair is related to Climb. Climb is related to Struggle. Struggle is a synonym of Fight. 
Spit <--RelatedTo--> Mouth <--RelatedTo--> Bite 
Wood <--RelatedTo--> Stair <--RelatedTo--> Climb <--RelatedTo--> Struggle <--Synonym--> Fight 