Speculate is a synonym of Guess. Guess is related to Action. 
Top is a type of Supply. Top is related to Eye. Eye is related to Bed. Bed is related to Tuck. 
Speculate <--Synonym--> Guess <--RelatedTo--> Action 
Supply <--IsA-- Top <--RelatedTo--> Eye <--RelatedTo--> Bed <--RelatedTo--> Tuck 