A Chinese student posted an apology on Sina Weibo on Monday after the speech she delivered at the commencement ceremony of the University of Maryland on Sunday went viral, triggering accusations of dishonesty and betrayal among many Chinese users on social media.

In her speech, Yang started by saying that whenever anyone asked her why she came to study at the University of Maryland, she always said: "Fresh air." The audience erupted in laughter.

"Five years ago, as I stepped off the plane from China, and left the terminal at Dulles Airport, I was ready to put on one of my five face masks, but when I took my first breath of American air, I put my mask away," she said.

Yang went on to say that the air she breathed in the US "was so sweet and fresh and utterly luxurious".

"I grew up in a city in China where I had to wear a face mask every time I went outside, otherwise I might get sick," said Yang, describing her hometown as heavily polluted.

Many Chinese students in the US believe that some facts Yang cited in her speech were somewhat stretched.

Yang, it was later revealed, hails from Kunming, in South China's Yunnan province, where air quality usually tops the national average.

"I also come from the city of Kunming, which is world famous for its good climate and weather," Zhang Jun, a PhD student at the University of Maryland, posted on his Facebook page on Sunday.

"Contrary to what she claimed, Kunming's air condition is near the top of most major cities in China. From my experience in the last few years, Kunming's air quality on average is at least as good as in Washington DC," Zhang added.

Luo Yi, a graduate student at Fordham University, wrote: "I considered the story Yang shared only as her personal story, not representative of all Chinese students in the US, not her school or any of her friend the air quality and cultural difference she had experienced cannot be generalized to anyone else's. Since I lived in a city with a relative better natural environment and an open cultural atmosphere, I didn't recognize the huge gap she mentioned."

Some Chinese students also expressed disappointment over the way Yang misrepresented China in her remarks.

"People in the US won't respect you if you don't respect your own country," said Zheng, a student at George Mason University.

Georgetown student Ning Ma wrote:"She grew up in China, but she does not know about China. She studied in the US for five years, but she does not understand the US."

"As an educated adult who should be able to think independently, she should understand that different countries have different systems, histories and backgrounds," said Zhang, who earned a master's from George Washington University in 2014.

There were 2,197 students from China at the University of Maryland for the 2016-17 academic year. Yang was one of the few Chinese students chosen to speak at the commencement.

Later Monday, Yang posted an apology on her Weibo account: "I was just sharing my experience as an international student in the US with no intention to deny or belittle my country or my hometown. I'm sorry about what I did and will learn from the mistake."

Yuan Yuan in Washington contributed to the story.

leshuodong@chinadailyusa.com