Length is related to River. River is related to Highway. you are likely to find Highway in/at/on Desert. 
Sit is a synonym of Welcome. Welcome is a type of Accept. Accept is related to Allow. 
Length <--RelatedTo--> River <--RelatedTo--> Highway --AtLocation--> Desert 
Sit <--Synonym--> Welcome --IsA--> Accept <--RelatedTo--> Allow 