Skin is related to Pale. Pale is related to Loose. Loose is the opposite of Exact. Exact is related to Only. 
Useful is related to Reading. Reading is a form of Read. Read is related to Clock. 
Skin <--RelatedTo--> Pale <--RelatedTo--> Loose <--Antonym--> Exact <--RelatedTo--> Only 
Useful <--RelatedTo--> Reading --FormOf--> Read <--RelatedTo--> Clock 