What does “modern” case mean?

Case is the grammatical function of a noun or pronoun. There are only three cases in modern English, they are subjective (he), objective (him) and possessive (his). They may seem more familiar in their old English form - nominative, accusative and genitive.

Explanation:

the maximum speed limit is 55 mph on a two-lane undivided highway and for vehicles towing trailers.

ichabod crane is a fictional character and the protagonist in washington irving's short story, "the legend of sleepy hollow", first published in 1820. in popular culture, this story is sometimes retitled as "the headless horseman."