To coin a phrase ...

At first glance, the kit which teaches Cantonese slang hardly seems likely to be a huge hit. The cards, which show old-fashioned pictures and short explanations, were invented by primary school teacher So Real Real - not his real name.

Since their publication this year, the kits, which cost HK$75, have sold like tickets to a Hins Cheung King-him concert and Mr So says he's overwhelmed by the response.

'In December last year, I joined a DIY book-making venture organised by the YMCA. I came up with a creative plan to make cards that would teach people Cantonese slang. I never expected they would be so popular,' says Mr So.

The cards have a retro design, with Chinese and English meanings of the phrase, and examples of usage. They are an easy way for people to learn colloquial expressions.

Mr So says his cards reflect the contemporary local youth culture and he hopes they will encourage people to explore it.

The 42 Cantonese expressions were gleaned through casual observation and selected by meticulous research.