Check is related to Mark. Mark is a synonym of Distinguish. Distinguish is a synonym of Separate. Separate is the opposite of Attach. 
Tide is a type of Run. Tide is related to Ocean. Ocean is related to Seal. Seal is a type of Decide. 
Check <--RelatedTo--> Mark <--Synonym--> Distinguish <--Synonym--> Separate <--Antonym--> Attach 
Run <--IsA-- Tide <--RelatedTo--> Ocean <--RelatedTo--> Seal --IsA--> Decide 