Most people in Hong Kong speaks Cantonese in their daily lives, which is a dialect from southern China. So, if you want to learn Cantonese, this is the place to be because you cannot avoid it, as you will hear it on buses, taxis, radios, TVs, shops, i.e. everywhere.
In recent years, more and more people have learnt to speak Mandarin and you often find people fluent in Mandarin in businesses and shops.
However, English-speaking visitors will not find it difficult to move about in Hong Kong as a vast majority of people in Hong Kong also can speak at least some English. This is partly because of Hong Kong's history and also because English is an important language medium in the business world in Hong Kong.
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