We've done the difficult part of the job.

我们已完成了工作的困难部分。

《牛津词典》

The difficult part is making up our minds now.

然而，当前我们面临的一个困难问题是转变我们的思想。

youdao

The difficult part is picking the one idea to go with.

困难的部分其实是挑选哪一个构思去实施。

youdao

When they reached New Guinea, they were about to begin the most difficult part of the trip.

VOA: special.2010.05.26

Part of the problem with using operant conditioning with babies is it's difficult to get them to behave in any systematic way.

应用操作性条件作用的部分问题在于,很难使婴儿们按照系统的方式行动

耶鲁公开课 - 心理学导论课程节选

What do you think is the most difficult part about studying English in the UK?

你觉得在英国，学习英语最难的部分是什么？

巴西的英语老师 - SpeakingMax英语口语达人

The difficult part is that researching individual municipal bonds takes time and effort.

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The difficult part is evaluating if the culture in that organization has evolved in a similar fashion to yours.

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The difficult part is in focusing your emotions consistently and clearly so that your gestures are equally clear and strong.

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