Extensive is similar to Large. Large is related to Poster. Poster is related to Bed. Rest requires Bed. 
Piano is related to Practice. Practice is the opposite of Test. 
Extensive <--SimilarTo--> Large <--RelatedTo--> Poster <--RelatedTo--> Bed <--HasPrerequisite-- Rest 
Piano <--RelatedTo--> Practice <--Antonym--> Test 