China Daily一篇文章有一段话【You've got mail ... and it's a postcard - China - Chinadaily.com.cn】：

Language is certainly a hurdle in postcrossing for many people - not only Chinese. For postcrossing to work on a global scale, a common communication language is needed so that everyone can understand each other. As cool as it may be to receive a postcard written in Chinese, the concept doesn't work if one doesn't understand it. Likewise, if you speak only Chinese, receiving a card written in Swedish takes part of the fun away. So a common language is required, and in postcrossing that's English since it's widely spoken.

Many people in China have limited exposure to English and that makes it (extra) hard to learn and practice it. That said, we know of many postcrossing members (including Chinese), who actually improved their English skills through their use of postcrossing.

其中一句话不太明白：As cool as it may be to receive a postcard written in Chinese, the concept doesn't work if one doesn't understand it.