Piano is a synonym of Soft. Soft is related to Wood. you are likely to find Wood in/at/on Fire. 
Guess is a type of Opinion. Opinion is related to Side. Side is the opposite of Top. Top is a synonym of Head. 
Piano <--Synonym--> Soft <--RelatedTo--> Wood --AtLocation--> Fire 
Guess --IsA--> Opinion <--RelatedTo--> Side <--Antonym--> Top <--Synonym--> Head 