There are many elements in Cantonese that make it suitable for humour, says Au Yeung.

A self-professed fan of actor-director Stephen Chow Sing-chi’s comedies and Dayo Wong Tze-wah’s stand-up shows, he says: “Both of them know a lot about Cantonese and use it to make people laugh.”

Plenty of road signs, restaurant menus and public notices display simplified Chinese characters to cater to Chinese residents and tourists. More significantly, about 70 per cent of 600 primary schools in Hong Kong and 40 per cent of its 500-plus secondary schools already use Putonghua for their Chinese-language lessons.

Some Hongkongers have tried to protect their mother tongue by developing web-based resources such as words.hk, an online Cantonese dictionary, and a pictorial representation of common Cantonese idioms.

Is Cantonese in danger? Hongkongers take steps to protect their heritage

Some may get the sinking feeling that defenders of the Cantonese language are simply fighting a rearguard action.

But that has not deterred academics such as Tang Sze-wing, vice-chairman of the department of Chinese language and literature at the Chinese University of Hong Kong. The department organised a month-long Cantonese festival in April, which featured seminars, book exhibitions and other activities celebrating the richness of the language.

Rather than hold consultations on whether Putonghua should be adopted as the medium of instruction for Chinese, “the government should boost frontline teachers’ knowledge of Cantonese instead”, Tang says.

“The current curriculum does not teach students about Cantonese as a language.”

While all Hongkongers can speak Cantonese, their pronunciation isn’t alway correct, and their

knowledge about it is lacking, Tang says.

“Cantonese as an academic discipline is rich. There are more than 40 functional words with no meaning in Cantonese, much more than Putonghua. Their combinations with other words reveal nuances in meanings. There’s also grammar in Cantonese which is worth exploring. Putonghua learners start by learning pinyin, [just as English learners by starting with phonetics for pronunciation]. But no one ever learns about Cantonese pinyin at school. So most locals do not know Cantonese [pronunciation], some locals use ‘lazy’ sounds’.”

Samuel Cheung Hung-nin, professor emeritus in the department of East Asian languages and cultures at the University of California, Berkeley, agrees.

“In the past, we didn’t feel the need to put emphasis on Cantonese teaching because there’s never a crisis. But there is now, as the language is under threat of being replaced,” says Cheung, who was invited to give talks during the Chinese University festival.

Hong Kong isn’t the only region where efforts to impose language policies have stirred anger over cultural hegemony, of course. In neighbouring Guangdong province, residents have staged several large-scale rallies in recent years in support of Cantonese, which is seen as being increasingly under threat. Similar protests were staged in 2014 after provincial television station Guangdong TV announced plans to broadcast the bulk of original programmes on its news channel in Putonghua instead of Cantonese.

Between 63 and 80 million people worldwide are estimated to speak Cantonese. Mandarin, or Putonghua as it is called in China, is the official language of China, but Cantonese has a much older lineage. Its pronunciation, vocabulary and usage is similar to the official language of the Tang dynasty (618-907). In fact, many Cantonese expressions and words are based on the elegant and refined sounds of classical Chinese, Au Yeung says.

“We use duplicated characters to describe colours in Cantonese like hung bok-bok for red. Such words originate from Shijing [or The Book of Songs], which is the oldest collection of Chinese poetry].

“Cantonese also includes lots of spot-on and funny descriptions. There are many expressions just to describe fat. This shows how rich our culture is.”

Although born in Jiangsu, Cheung is also a great admirer of Cantonese, having grown up in Hong Kong himself.

“In English, [the younger generation call older relatives] uncle or auntie. But in Cantonese, there are minute classifications for your parents’ siblings. It’s fun,” Cheung says.

“Cantonese is a tonal language. The tonal differences reveal [nuances in] meaning. Among the many Chinese dialects, only Cantonese enjoys the same status as Putonghua.

“Hokkien [or Fujianese] is widely spoken in Taiwan. But on formal occasions such as academic conferences, the people always switch to Putonghua. Hokkien is used only in casual conversation.

“The same is true for Shanghainese. Many children in Shanghai don’t even know how to speak Shanghainese now. Do we want to see Hong Kong go the same way as Shanghai?”

More parents are speaking to their children in English or Putonghua at home, the better to prepare them for school, but Tang argues Hongkongers should do their best to use Cantonese for everyday communication.

“The passing of a language to future generations requires the efforts of all. If there are fewer and fewer people who speak Cantonese, it will lose vitality and die.”

Thanks to the effort of educators like Au Yeung, young Hongkongers are showing greater interest in their mother tongue. His Cantonese course at Chinese University is very popular, with more than 100 students signing up each semester.

“It’s a general knowledge course open to all students in the university. I teach grammar, pronunciation but also hip expressions used by youngsters now. I also teach them to use Cantonese to write lyrics. It’s quite a challenge, as Cantonese has nine tones and matching the melody with the word with the right tone can be difficult.”

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