这对于习惯了“免费服务”的中国电子书市场，将是一个巨大挑战。

It will be a big challenge for China's e-book market that has been used to free service.

youdao

这对于习惯了“免费服务”的中国电子书市场，将是一个巨大挑战。

It will be a big challenge for China's e-book market that has been used to free service.

youdao