Attitude can be the biggest language barrier

Due in part to the blessing of a Hong Kong wife, Chris Lonsdale speaks fluent Cantonese, well enough to get him onto a cooking programme on a Chinese channel that invites stars to show their favourite dishes.

This skill puts him in a small minority among the gweilo community, and for this he blames Hong Kong people. 'The attitude of Hong Kong people is the biggest reason. They do not encourage foreigners to speak Cantonese at all. They laugh at them and pick faults.

'It is better in Guangzhou. If people do not use it with you and you get no response, you cannot learn. Since 1997, more foreigners have made the effort,' he said.

'If you speak to a Hong Kong person in Putonghua, he will reply in Putonghua because he also wants to learn and it is a neutral language.'

Mr Lonsdale has two explanations for the way Hong Kong people react - a mental filter that a foreigner cannot be speaking Cantonese and also a sign of pride that they can speak English.

His advice to those who want to learn is to buy his book, The Third Ear, and find partners who will use Cantonese with you.

Worldwide, more than 30 million people are estimated to be learning Putonghua. This has created an enormous industry of institutions, companies and teachers offering this course. Since 2004, the mainland has opened more than 50 Confucius Institutes in 28 countries, to promote its language and culture. So, given the choice, many foreigners living here choose Putonghua.

But Mr Lonsdale warns that things are changing in major cities on the mainland.

When he was a student in Beijing in the 1980s, few people could speak English and so he had many happy to teach him Putonghua.

But the cities are becoming like Hong Kong. 'It's hard to practise Putonghua as many people want to speak English.'