Knowledge is related to Know. Know is related to Learning. Village can be used for Learning. Village is related to Chief. 
Informal is a synonym of Casual. Casual is related to Remark. Remark is related to Mark. 
Knowledge <--RelatedTo--> Know <--RelatedTo--> Learning <--UsedFor-- Village <--RelatedTo--> Chief 
Informal <--Synonym--> Casual <--RelatedTo--> Remark <--RelatedTo--> Mark 