Ethnic is a type of Person. Person is related to Male. Male is related to Man. Man is related to Doll. 
Sentence is created by Person. you are likely to find Period in/at/on Sentence. Period is the opposite of Frequency. 
Ethnic --IsA--> Person <--RelatedTo--> Male <--RelatedTo--> Man <--RelatedTo--> Doll 
Person <--CreatedBy-- Sentence <--AtLocation-- Period <--Antonym--> Frequency 