Invasion is a type of Spread. Spread is a synonym of Gap. Gap is a synonym of Tear. Tear is a type of Rush. 
Poem can be used for Class. Poem can be used for Romance. 
Invasion --IsA--> Spread <--Synonym--> Gap <--Synonym--> Tear --IsA--> Rush 
Class <--UsedFor-- Poem --UsedFor--> Romance 