English is difficult to learn at the beginning.

英语刚开始学起来很难。

youdao

Jim, is physics difficult to learn?

吉姆，物理难学吗？

youdao

All languages are difficult to learn.

所有的语言都很难学。

youdao

CPR is not difficult to learn.

VOA: special.2009.08.11

Because there are no articles in the Korean language, so that makes it really difficult to learn them in English.

因为韩语里面没有冠词一说，所以对他们来讲学习英语冠词真的很难。

韩国人经常犯的失误 - SpeakingMax英语口语达人

Other languages don't have that distinction and so those distinctions are very difficult for non-native English speakers to learn.

其他语言并没有这样的差别,所以非英语母语的说话者,很难发现这些差别

耶鲁公开课 - 心理学导论课程节选

But stenography is a steep learning curve and more difficult to learn than Qwerty.

BBC: Why do we all use Qwerty keyboards?

I've never seen Cornish written out and to look down at it on paper, it was difficult to learn.

BBC: Cornwall's Bitter Sweet premiere

It can be expensive and slow to grow, as the language has the reputation of being very difficult to learn.

NPR: Chinese Classes Grow in Popularity with U.S. Students