Brain can be used for Think. 
you are likely to find Carpet in/at/on Bed. you are likely to find Dirt in/at/on Carpet. Dirt is related to Flower. Flower is related to Bunch. 
Think <--UsedFor-- Brain 
Bed <--AtLocation-- Carpet <--AtLocation-- Dirt <--RelatedTo--> Flower <--RelatedTo--> Bunch 