Hay is related to Dry. Dry is related to Desert. Desert is related to Sun. you are likely to find Cat in/at/on Sun. 
Yield is a synonym of Crop. Crop is related to Plant. Plant is a different concept from Vegetable. 
Hay <--RelatedTo--> Dry <--RelatedTo--> Desert <--RelatedTo--> Sun <--AtLocation-- Cat 
Yield <--Synonym--> Crop <--RelatedTo--> Plant <--DistinctFrom--> Vegetable 