A parent expresses fright upon hearing thunder, and the child sees this fear and develops the fear for himself.

父母一听到雷声就表现出受惊吓，孩子看到这种害怕后会则会发展出对他自己来说的害怕。

youdao

We fear for his safety.

我们担心他的安全。

《牛津词典》

Fear for the safety or well-being of yourself and others you care about, e.g. your parent or your brothers and sisters.

担心你和你关心的人的安全或幸福，例如你的父母或兄弟姐妹。

youdao

and fear for the family of a very frightening little girl.

VOA: special.2009.06.12

And I want to deal with fear for different reasons.

分析愤怒的不同原因。

耶鲁公开课 - 心理学导论课程节选

It is fear, not reason, that leads us to abandon the state of nature and sue for peace.

与理性不同，恐惧让我们放弃自然状态,转而去寻求和平。

耶鲁公开课 - 政治哲学导论课程节选

It appears she is not the only bride in fear for her big day.

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There are times I fear for the governance of the continent I inhabit, I really do.

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"I fear for my future, because I need to keep working, " she said in one post.

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