The 'Open Yale courses' online programme allows people around the world to access lectures by distinguished teachers and scholars at Yale University, along with other course material.
Despite the fact all the lectures are in English, these recordings have become some of the hottest videos on the mainland.
This is partly thanks to a group of translators, YYeTs, who provided subtitled translations of the lessons.
Cean (who declined to give her full name) is a voluntary member of the group.
She is a full-time English editor who joined the group in 2008. She has also produced Chinese-English subtitles for American and European TV dramas.
'I am glad the courses are so popular,' she says.
'By providing translations, we let more people enjoy good television shows. I like sharing good things with others.'