one thing you do when you Surprising is Laugh. Laugh is the opposite of Frown. 
Shower is a type of Party. Shower is a type of Provide. Provide is a type of Give. Give is the opposite of Obtain. 
Surprising --HasSubevent--> Laugh <--Antonym--> Frown 
Party <--IsA-- Shower --IsA--> Provide --IsA--> Give <--Antonym--> Obtain 