Detail #20: Complements and implicit case

A hierarchy-like thing where nouns, when operating as complements assume implicit case, so e.g.

I am town = I am in town

He becomes town = He goes to town 

This would probably interact with nouns and verbs in various complicated ways, and could possibly fit well with an isolating language, so I may include it in the isolating language I am planning. This differs from topic-comment in some ways, which I should probably explain in greater detail but this'll be enough for tonight.

Notice that this should only go for complements, and not for adverbs, in the language in question.