Sword is related to Slice. Slice is related to Portion. Portion is related to Part. Part is related to Arm. 
Sleep is related to Trailer. Trailer is related to Trash. Trash is related to Glad. Glad is the opposite of Unhappy. 
Sword <--RelatedTo--> Slice <--RelatedTo--> Portion <--RelatedTo--> Part <--RelatedTo--> Arm 
Sleep <--RelatedTo--> Trailer <--RelatedTo--> Trash <--RelatedTo--> Glad <--Antonym--> Unhappy 