Trail is related to Park. you are likely to find Bank in/at/on Park. Bank is the opposite of Casino. 
Educational is related to Lecture. Lecture is a synonym of Discourse. Discourse is a type of Cover. 
Trail <--RelatedTo--> Park <--AtLocation-- Bank <--Antonym--> Casino 
Educational <--RelatedTo--> Lecture <--Synonym--> Discourse --IsA--> Cover 