Zhang Tiantian, 24, an English trainer from Shanghai

Zhang grew up in Shanghai, while his parents are from nearby Jiangsu province and have stayed in Shanghai for more than 20 years.

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In most cases, Zhang's parents speak Mandarin. Rarely do they speak their own dialect, even if they are at home.

"They hardly had a chance to speak it and thus lost the habit of using it," Zhang says.

Zhang speaks Mandarin with his parents at home while speaking Shanghai dialect with his friends and colleagues. He acquired the Shanghai dialect from his teacher, who is a Shanghai native.

Zhang used to speak a little of his parents' original dialect when he was very young but is unable to speak it now.

"It's because I don't have the environment to use it and don't have someone to talk with," Zhang says.