Settle is a synonym of Compound. Gas is a type of Compound. Gas can Expand. 
Dust is related to Light. Light is related to Reflection. Reflection is related to Double. Double is related to Pair. 
Settle <--Synonym--> Compound <--IsA-- Gas --CapableOf--> Expand 
Dust <--RelatedTo--> Light <--RelatedTo--> Reflection <--RelatedTo--> Double <--RelatedTo--> Pair 