This word, whom, it isn’t the easiest word to throw around, and I’m willing to bet about 99% of English speakers would prefer to just say who rather than risk looking like a dumbass. Even the dictionary thinks you should lay off before attempting to tackle this beast: “Although there are some speakers who still use who and whom according to the rules of formal grammar as stated here, there are many more who rarely use whom at all; its use has retreated steadily and is now largely restricted to formal contexts.” One of my best teachers in high school told me that you can tell if whom is the right word to use if you can replace it with him—to whom are you speaking? to him are you speaking? are you speaking to him?—because both whom and him “forms the objective case”; in other words, he is the subject, him is the object, as in, he is screwing himself. The subject screws the object.
Actually my teacher didn’t quite explain it like that, and I still didn’t really get whom until I got hitched to a Korean princess and started learning the most difficult major world language for English speakers. Over the years I encountered the word who, which in Korean is noogoo, and also ran into Korean’s pesky articles, of which there are three—ga, neun, and leul, rough equivalents of the and a in English, though they come after the noun instead of before the noun and are actually called particles. Ga (which alternates with ee) is almost completely inexplicable and doesn’t seem to have an English equivalent (it should be spelt: “Gah!”), but neun and leul are, roughly speaking, markers for the objective and subjective cases; noogoo-neun is who, and noogoo-leul is whom. Once I figured this out, I figured out whom, and felt more comfortable deploying it in my writing, though speaking the word out loud smacks of grammatical pretension.
So as you can see, spending hundreds of hours pouring over Korean textbooks and sparring with my Korean wife in her own tongue wasn’t a complete waste of time; most English teachers, when they come here, regard the language as too daunting and too pointless to attempt—I was once one of them—and manage to get by for years without speaking more than a few words. This knowledge of whom is proof that fruit will be born from your labors, should you get to work on the Korean language; but aside from being able to say the word “logical” for my students, and aside from being able to thank the older citizens of Gyeongju for participating so competitively in their daily staring contests with me (chodaba joo-shyuh-saw kamsamneeda), and aside from being able to chat with my in-laws, I’m not quite sure I can think of any others.