It is more difficult to practise in winter.

冬天练习更困难。

A moral dilemma is a situation in which you have two or more difficult choices to make.

道德困境是指你需要做出两个或更多困难选择的情况。

It is more difficult to practise in winter because the days are short and the weather is cold too.

冬天练习更困难，因为白天短，天气也冷。

The awn can make harvesting more difficult.

芒会使收割更加困难。

As you age, staying healthy becomes more and more difficult.

随着年龄的增长，保持健康变得越来越难。

The examen was more difficult than I expected.

这次考试比我预期的要难。

Their inexperience made the task more difficult.

他们的缺乏经验使得任务变得更加困难。

This path is shorter but more difficult to walk.

这条路比另一条较短的，但更难走。

Metastatic tumors are often more difficult to treat.

转移的肿瘤通常更难治疗。

The cleanup process was more difficult than expected.

清理过程比预期的更困难。