Person wants (to) Mom. Person wants (to) Computer. Computer is related to Level. Floor can be Level. 
you are likely to find Gate in/at/on Backyard. Backyard is a type of Yard. Yard is related to Year. Year is related to Annual. 
Mom <--Desires-- Person --Desires--> Computer <--RelatedTo--> Level <--HasProperty-- Floor 
Gate --AtLocation--> Backyard --IsA--> Yard <--RelatedTo--> Year <--RelatedTo--> Annual 