Even if you don't understand a word of Mandarin, it was easy to spot the occasional "um" and "sorry" littered in Facebook chief executive Mark Zuckerberg's speech. But during a question and answer session at Tsinghua University in Beijing, he kept at it  — for 30 very long minutes.

For the audience of Chinese students, Zuckerberg's first words in Mandarin clearly came as a huge shock. He was introduced as he might be in most places he travels: in English. Polite applause followed, then Zuckerberg opened his mouth and the first words tumbled out.

The audience chuckled, clapped, then exclaimed with delight when it became clear that he wasn't going to stop.

Now, this Washington Post writer doesn't know a single word in Mandarin — a notoriously difficult language to learn and particularly, to speak. But it's clear that the amount of effort and determination it takes to conduct a half-hour interview in a second language is akin to taking your oral foreign language exam in front of dozens of native speakers and millions of people in the peanut gallery.

But it isn't just Zuckerberg's linguistic acrobatics that make this a notable moment. This small gesture — although some would argue that it is a huge moment — is perhaps his strongest foray into the battle for hearts and minds in China.

Zuckerberg and Facebook have for years been aggressively courting Chinese users and the potential financial upside for the business. Although Beijing has mostly banned Facebook, the company signed a contract for its first office in China earlier this year. 

They know that it is likely to be a long fight — on regulatory, political and cultural battlefields — to gain a foothold in China. But on Wednesday, Zuckerberg showed a personal commitment to Mandarin that will reverberate across the world. And it clearly charmed his Chinese audience.

So how well did he actually do? Unsurprisingly, the world has some thoughts — with a capital "T" — about Mark Zuckerberg's Mandarin.

Over at Foreign Policy, another Mandarin speaker rates Zuckerberg's language skills at a seventh grader's speech:

It's hard not see a patronizing note in the Chinese audience's reaction to Zuckerberg's Mandarin. To borrow from Samuel Johnson's quip, he was like a dog walking on its hind legs: It wasn't done well, but it was a surprise to see it done at all.

From a purely observational perspective, Zuckerberg managed to maintain the cadence of a comfortable public speaker — although The Washington Post's William Wan noted that he largely avoided the complex tones of the language and spoke grammatically as if he were conversing in American English.

He clearly struggled as some points in the session. But he was still able to make the audience laugh throughout — and not always at his expense.

At one point, his host appeared to ask a question he couldn't understand — so he thought about it, waited for a more simple explanation of the question, then continued answering in Mandarin. The audience gamely corrected his pronunciation, supplied missing vocabulary and played along in Mandarin, even though most could probably speak English.

The move shouldn't come as a total surprise given that Zuckerberg has talked publicly about his efforts to learn Mandarin since 2010. Asked why he decided to study Chinese, Zuckerberg explained, according to Quartz, that it was about three things: "1) to speak with his grandma-in-law and other in-laws; 2) China is a great country, and he wants to study its culture; 3) Chinese is hard, and he loves challenges."

And it goes without saying that most Americans, for whom English is a first language, will never learn Mandarin. And notably when the Chinese students in the audience stood to ask their questions, they all spoke in clear English.

[The headline of this post has been updated. Initially we characterized Zuckerberg's Mandarin as "terrible," but upon further review, it has been upgraded to "mediocre."]