One of the things I loved about working with Katharine on the textbook is that she always knows the answer to grammar question — not just knows the answer, which I usually know intuitively, but can explain the answer.

This sentence stumped me:

The F.B.I. also arrested two of Mr. Rahim’s associates, whom prosecutors say were involved in the plot.
From: One by One, ISIS Social Media Experts Are Killed as Result of F.B.I. Program

That “whom” sounded wrong.

Usually, when something sounds wrong to me, it is wrong. But then, when I read the sentence again, thinking about its grammar, I wasn’t sure.

Wasn’t that “whom” the direct object of “say“?

Whom” is the direct object form. Not “who.”

I’ll post Katharine’s explanation tomorrow. (Or make her do it!)