Comments by "Good Citizen" (@GoodCitizen-gm1tl) on "How China's first home-made train wheels are revolutionizing high-speed rail" video.

Most of us in China learn English in schools and forget most of them after graduation, because if a language isn't being used in real life, it gets rusty in your brain and later you forget them. In China, English isn't being used in real life if you are not an English teacher or involved in international trade or affairs. Chinese people use Mandarin in real life and may speak their hometown dialects with their families or hometown fellows (most of these dialects are near-Mandarin and are largely mutually intelligible. However some eastern and southern dialects are way different and are not mutually intelligible with Mandarin, like Cantonese, Hokkien, Shanghaiese and others, but their native speakers can always choose to speak Mandarin as it is the only lingua franca in China)
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Most of us in China learn English as a mandatory subject in schools and tend to forget most of them some time after graduation, because if a language isn't being used in real life, it gets rusty in your brain and later you forget them. In China, English isn't being used in real life if you are not an English teacher or involved in international trades or affairs. Chinese people use Mandarin in real life and may speak their hometown dialects with their families or hometown fellows (most of these dialects are near-Mandarin and are largely mutually intelligible. However some eastern and southern dialects are way different and are not mutually intelligible with Mandarin, like Cantonese, Hokkien, Shanghaiese and others, but their native speakers can always choose to speak Mandarin as it is the only lingua franca in China). As urbanization is rapidly ongoing in China, many dialects are disappearing because the rural residents, when moved into cities, lost their linguistic enviornment for their dialects and have to speak Mandarin with others, their children grow up by speaking only Mandarin.
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