Effort is a synonym of Sweat. one thing you do when you Ski is Sweat. Ski is related to Board. 
Building is related to Bridge. you are likely to find Homeless in/at/on Bridge. Homeless is related to Beg. 
Effort <--Synonym--> Sweat <--HasSubevent-- Ski <--RelatedTo--> Board 
Building <--RelatedTo--> Bridge <--AtLocation-- Homeless <--RelatedTo--> Beg 