The heart of the problem is supply and demand.

问题的核心是供给和需求。

《柯林斯英汉双解大词典》

I thank you from the bottom of my heart for helping me solve this problem.

我从心底感激你帮助我解决这一问题。

youdao

Being overweight increases the risk of having a heart problem.

超重会增加患心脏病的风险。

youdao

So, many people have relatives they know of that have had to have their heart imaged -- heart disease is a major problem in the United States, and there's a good chance that they had Cardiolite given to them to help in that imaging process.

它被用在心脏成像中,很多人都有一些亲戚他们-,必须要做心脏成像，心脏病已经是美国的一个主要问题,而很有可能他们就要用到Cardiolite来成像。

麻省理工公开课 - 化学原理课程节选

To get to the heart of the problem of US schools, we need to be thinking through more fundamentally: What is the goal of education?

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While that was certainly the genesis of the problem, it hardly gets to the heart of a problem that seems to speak more to culture than execution.

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At the heart of the problem is a lot of debt that really cannot be repaid.

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