Bridge is a type of Connect. Rest is a type of Bridge. Rest is related to Nest. Nest is related to Habitat. 
Qualify is a type of Add. String is a type of Add. String is related to Like. Like is related to Walking. 
Connect <--IsA-- Bridge <--IsA-- Rest <--RelatedTo--> Nest <--RelatedTo--> Habitat 
Qualify --IsA--> Add <--IsA-- String <--RelatedTo--> Like <--RelatedTo--> Walking 