Facebook founder Mark Zuckerberg's attempt to woo a Chinese audience by speaking Mandarin has had mixed reviews from Chinese speakers.
News outlet Quartz described his 30-minute chat as making him sound "like someone was stepping on his face".
Others were kinder. "This CEO is so cool, I want to cry," wrote one.
Fellow chief executive - Apple's Tim Cook - was also in China, questioning officials about an alleged hack of its iCloud service.
Mr Zuckerberg was in Beijing as a newly appointed member of the advisory board for Tsinghua University School of Economics and Management.
As part of that role, he met students for a 30-minute chat, which he conducted in Mandarin.
There was plenty of reaction to his attempts to communicate in Chinese.
One blogger wrote: "It's hard to describe in English what Zuckerberg's Mandarin sounded like but I'd put it roughly at the level of someone who studied for two years in college, which means he can communicate like an articulate seven-year-old with a mouth full of marbles."
Others commented: "Oh my god... this is terrible... but apart from the tones, he seems to have learnt the vocabulary and grammar pretty well."
One tonal slip-up led Mr Zuckerberg to claim that Facebook had just 11 mobile users instead of one billion.
While most agreed that his pronunciation was far from fluent, most were also impressed that he had attempted it at all.
Mr Zuckerberg, who is married to Chinese-American Priscilla Chan, set himself the goal of learning Mandarin in 2010, in part so that he could communicate with his Chinese relatives.
But Facebook as a company is also keen to improve relationships with China. There is currently a ban on the use of the social media site, which dates back to 2009.
There was no explicit chat about the ban and Mr Zuckerberg described China as a "great country".
"The Chinese language is difficult, and I speak English, but I like challenges," he said.
On Facebook's future in the country, he was diplomatic: "We are already in China. We help Chinese companies gain customers abroad. We want to help the rest of the world connect to China," he said.
Fellow chief executive Tim Cook is also in China and will attend a meeting at Beijing's Tsinghua University with Mr Zuckerberg later in the week.
Meanwhile he has had talks with the vice premier of China to discuss protecting user data in the wake of recent alleged hack attacks targeting iCloud users.
The attacks were revealed by Chinese activist group GreatFire.org, which accused the Chinese government of being involved.
iCloud user data was collected by creating a spoof icloud.com website.
Mr Cook also used the trip to China to visit Foxconn's iPhone factory and said that the company would open 25 retail stores in China in the next two years.
Apple currently earns about 15% of its revenue in China.