A mathematics university professor discovered the hard way that silence is not always golden.

After giving a two-hour zoom lecture, Professor Dong Wang of the National University of Singapore soon realized that none of his students had heard a word because their mike was silent, local Independent news outlets reported.

Wang then asked around 20 students who were actually involved with the online class throughout the case – and got nothing but a wicket.

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“No … uh … can we finish our class?” He asked.

Eventually, some students spoke up and told him that he had been mute the whole time.

“We can’t hear anything from you since 6:08,” a student told the innocent professor.

“What from?” Wang asked the student, who confirmed the time. “You mean, how long did you listen?”

One student replied that he initially listened only at 6 pm, and nothing else as his screen fraze from 6:08 pm.

An obviously flustered Wang then told the class that he would repeat the entire lecture a second time.

One of the students, Azusa Chan, told the news outlet that the professor inexplicably killed himself.

The student said, “The students made every effort to deflect attention and even to tell their phone number. However, she did not give any answer and continued the lesson.”

“The count of contestants kept decreasing over time, as the students could not contact the professor and had no other recruitment. You see here that there are 20+ students who wait two hours for the professor to return , “Said Chan.

The student reported that Wang was doing full text on an iPad, “so you can expect many things to go wrong on such a setup.”

“After this incident, he left [sic] Whenever he is giving a lecture, he has his phone so that we can call him in an emergency.

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