Alexander James Adams has a song which is quite nice yet makes me grate my teeth. Its refrain is “There’s only the music between you and I.” An occasional grammatical violation in a song is OK, but one that occurs in every verse is painful. There are plenty of good rhymes for “me.”

When a pronoun follows a preposition, it has to be in the accusative case, also called the objective case. “With me.” “To them.” “Behind her.” The favorite grammatical error of snobs is to use the nominative case instead.

No one makes the error in the simplest form. Even toddlers never say “for I.” (There are a few exceptions in song. “I Wonder as I Wander” uses “like I.” Gilbert and Sullivan must have done it somewhere for a humorous effect.) It crops up almost exclusively in two situations: compound objects and modifying clauses.

Between we

The rule for compound objects is exactly the same as for simple objects. It’s “between us,” not “between we.” Likewise, it’s “between you and me,” not “between you and I.” This error usually occurs with “between.” People think getting it wrong makes them sound cultured.

On he

The other error is more complicated to explain. I ran into it recently in the maxim, “The burden of proof is on he who asserts the positive.” “He” is the object of the preposition “on,” so it should be “him.”

The modifying clause confuses people. They think “he” is the subject of the clause “he who asserts the positive.” But the clause is actually “who asserts the positive,” and it modifies the pronoun “him.” It’s easier to see when the clause is non-restrictive and set off by a comma: “The burden of proof is on Smith, who asserted the positive.”

This one’s tricky, since “him who …” sounds wrong to many. Some people might argue that “on he who…” is correct because it’s used so much. But that means devising a special grammatical rule for a very narrow case. We say “on him,” so why change it when the pronoun has a modifying clause? English is confusing enough already.

Better than who?

Here’s one where I go the other way. Should you say “No one is more qualified than she” or “No one is more qualified than her”? Traditional grammarians might say that “than” is a conjunction and there’s an implied “is” after “she”, creating a subordinate clause.

Most people would say “than her,” and it makes perfect sense if you consider “than” a preposition rather than a conjunction. Merriam-Webster recognizes “than” as a preposition meaning “in comparison with.” “Than her” is absolutely correct.

I won’t say “more qualified than she” is wrong, but it sounds archaic and isn’t required. If it gives you a better rhyme, go for it. But please don’t use “between you and I” to get a rhyme. Sorry, Alex.