difficulty of learning

例句：

1. 1. The task of learning a new language is often difficult for many people.
   学习一门新语言的任务对许多人来说往往是困难的。
2. 2. The project faced numerous difficulties during the implementation phase.
   该项目在实施阶段遇到了诸多困难。
3. 3. To succeed in this field, one must overcome many difficulties and challenges.
   要在这个行业取得成功，一个人必须克服许多困难和挑战。