Comment is related to Note. Note is related to Text. Text is related to Phrase. 
Structural is related to Bone. Bone is related to Strength. Strength is related to Quality. 
Comment <--RelatedTo--> Note <--RelatedTo--> Text <--RelatedTo--> Phrase 
Structural <--RelatedTo--> Bone <--RelatedTo--> Strength <--RelatedTo--> Quality 