USC professor under fire after using Chinese expression students allege sounds like English slur

The University of Southern California, photographed in 2018.

(CNN)A business professor at the University of Southern California became the center of an international academic controversy last weekend, after ​the school administration received a letter accusing him of using Chinese words that sounded like an English racial slur. ​

The letter was not signed by any individuals, but instead by "Black MBA candidates c/o 2022."
CNN obtained a copy of the letter, but could not find an official USC group by that name or reach the letter-writers for comment.
    Professor Greg Patton of USC's Marshall School of Business was teaching a ​communications class via Zoom call on August 20, according to the university. An online video recording of the call, which USC confirmed was authentic, shows Patton ​discussing the use of pauses while speaking, and giving an example of how Chinese ​speakers use filler words.
    "In China, the common word is 'that' -- that, that, that, that," he said in the video, before using the equivalent Chinese term nei ge several times to demonstrate.
    The following day, a complaint was filed to the school administration, saying the term sounded like the N-word and that Patton had "offended all of the Black members of our class."
    Headshot for Greg Patton, Professor of Clinical Business Communication at University of Southern California's Marshall School of Business.
    "This phrase, clearly and precisely before instruction is always identified as a phonetic homonym and a racial derogatory term, and should be carefully used, especially in the context of speaking Chinese within the social context of the United States," ​according to the letter, which accused Patton of negligence.
    "The way we heard it in class was indicative of a much more hurtful word with tremendous implications for the Black community."
    The video of the class has since been circulated widely online, even spreading on Chinese social media, with Chinese viewers defending Patton's use of the phrase and expressing confusion about why it ​was viewed as problematic.
    A week later, Marshall School Dean Geoffrey Garrett announced that a different professor would take over teaching Patton's class for the rest of the semester, in an email to students that was shared with CNN.
    "Professor Greg Patton repeated several times a Chinese word that sounds very similar to a vile racial slur in English," said Garrett in the email. "Understandably, this caused great pain and upset among students, and for that I am deeply sorry. It is simply unacceptable for faculty to use words in class that can marginalize, hurt and harm the psychological safety of our students. We must and we will do better."
    Garrett added that he was "deeply saddened" by the "disturbing episode," and that any students uncomfortable with staying in Patton's class would have alternative options to complete their academic requirements.
    A sign for USC's Marshall School of Business.
    A USC Marshall spokesperson told CNN that Patton has not been suspended from teaching; he has only stepped away from the specific course in question, and continues to teach his other classes.
    "We acknowledge the historical, cultural and harmful impact of racist language," said USC Marshall in a statement. "The faculty member agreed to take a short term pause while we are reviewing to better understand the situation and to take any appropriate next steps."
    In a subs