I've heard from many sources that it can be both challenging an enjoyable to gain fluency in a non-native tongue.

我从很多方面了解到这样能激发快乐，也能使说外语的舌头更灵活。

youdao

I've heard from many sources that it can be both challenging an enjoyable to gain fluency in a non-native tongue.

我从很多方面了解到这样能激发快乐，也能使说外语的舌头更灵活。

youdao