Lemon is a type of Fruit. Hip is a type of Fruit. 
Mouth is related to Bill. Bill is related to Mortgage. Mortgage is related to Interest. Interest is a synonym of Concern. 
Lemon --IsA--> Fruit <--IsA-- Hip 
Mouth <--RelatedTo--> Bill <--RelatedTo--> Mortgage <--RelatedTo--> Interest <--Synonym--> Concern 