In English dialects, there are subtle differences between the meanings of one of these three words. If you go back some seventy years, the phrase "Is he yet reading?" would have been understood differently in Ohio and in New England.

In New England, this phrase would have been understood as a stilted way of saying, "Is he reading yet?", something one would say of a child.

In Ohio, it meant, "Is he still reading?", something one would say of an old man.

The matchup for ya, aún, and todavía is close but not exact. You shouldn'r expcet it to be exact. With prepositions, the mismatches are even more evident.

In English dialects, there are subtle differences between the meanings of one of these three words. If you go back some seventy years, the phrase "Is he yet reading?" would have been understood differently in Ohio and in New England.

In New England, this phrase would have been understood as a stilted way of saying, "Is he reading yet?" something one would say of a child.

In Ohio, it meant, "Is he still reading?" something one would say of an old man.

The matchup for ya, aún, and todavía is close but not exact. You shouldn't expect it to be exact. With prepositions, the mismatches are even more evident.