Single is related to Bolt. Bolt is related to Useful. Drug can be Useful. 
Reduce is related to Action. Action is related to Join. Join is a synonym of Combine. Combined is derived from Combine. 
Single <--RelatedTo--> Bolt <--RelatedTo--> Useful <--HasProperty-- Drug 
Reduce <--RelatedTo--> Action <--RelatedTo--> Join <--Synonym--> Combine <--DerivedFrom-- Combined 