Fragment is a synonym of Catch. Catch is a type of Perceive. Perceive is a type of Understand. 
Tunnel is related to Hole. Hole can be One. One is related to Lip. Lip is related to Muscle. 
Fragment <--Synonym--> Catch --IsA--> Perceive --IsA--> Understand 
Tunnel <--RelatedTo--> Hole --HasProperty--> One <--RelatedTo--> Lip <--RelatedTo--> Muscle 