STI and Resources

Perhaps someone can share some insight:

I'm modeling a simple English-Japanese dictionary. Phase 1 is simple.

There are Entries, but I need to keep in mind that verbs, nouns,
adjectives all conjugate differently. I need some place for that
logic code in the future.

Entry:
t.string 'type', 'english', 'japanese'

So I chose single table inheritance. It gives a model for each word
type and I can put the methods needed for future tools, quizzes, etc.
there.

However, alot of trouble follows. I have to handle the entry type and
instantiate the proper class in the create method. doable. But now
all of simply_helpful looks at my object and wants to render things
like 'noun_url' instead of 'entry_url'.

I don't feel that I need to map every word type in the routes. I only
need one controller.

Thoughts?