Gathering is related to Assemble. Assemble is a synonym of Piece. Piece is related to Paper. 
Wave is related to Shore. Shore is a type of Beam. Beam is related to Rod. Rod is related to Bar. 
Gathering <--RelatedTo--> Assemble <--Synonym--> Piece <--RelatedTo--> Paper 
Wave <--RelatedTo--> Shore --IsA--> Beam <--RelatedTo--> Rod <--RelatedTo--> Bar 