When Mark Zuckerberg spoke Chinese during an appearance Wednesday at Beijing's Tsinghua University, the Facebook CEO smiled and dismissed his linguistic chops. "My Chinese is really zaogao," he said, using the idiomatic term "spoiled cake" for "terrible." The audience cheered, impressed he could say anything at all.

As it turned out, Zuckerberg's Chinese wasn't half bad. The Facebook CEO was able to converse in the language for a half-hour, impressing the audience despite some stumbles with grammar and pronunciation. Foreign Policy's Isaac Stone Fish, a Mandarin-speaker, rated his Chinese as equivalent to that of a second-year college student, while several experts polled by The Washington Post more or less agreed. But Zuckerberg isn't in college. He's the CEO of a $200 billion company based in the United States learning a language that requires the average English-speaker much more time to learn than a European tongue.

Zuckerberg claims a strong interest in Chinese culture. His wife, Priscilla Chan, is an American of Chinese descent, and Zuckerberg is an avowed fan of martial arts star Huo Yuanjia.

But his interest is more than merely personal. Five years after China blocked Facebook, the company retains significant business interests in the country. Chinese app developers have used Facebook as a platform for mobile app installation ads, a large and growing business. The company also maintains a presence in Hong Kong, where 61 percent of the population uses Facebook, and was reportedly seeking to open a sales office in Beijing.

Even if China's government unblocks Facebook, the company faces a more competitive Chinese tech scene than ever before. Both Sina Weibo, China's Twitter, and WeChat, a chat service that resemble Facebook's own WhatsApp, boast user bases in the hundreds of millions. At Xinhua, Zuckerberg cited several Chinese companies, including WeChat's Tencent, as examples of companies whose innovation he admired.

Whatever Facebook's plans for China may be, Zuckerberg's linguistic ability seems to signal that, at least, the CEO did not let the firewall deter him.

"This is not a hobby," said Emily Parker, an expert on China's Internet, on Twitter. "It's a business mission."