Ocean can be used for Swimming. one thing you do when you Swimming is Float. Float is a type of Artifact. 
Island is related to Statue. Statue is related to Big. Big is related to Station. 
Ocean --UsedFor--> Swimming --HasSubevent--> Float --IsA--> Artifact 
Island <--RelatedTo--> Statue <--RelatedTo--> Big <--RelatedTo--> Station 