It's only fair to let her know that you intend to apply.

让她知道你有意申请是很公平的。

《柯林斯英汉双解大词典》

I'm going to call Mum to let her know we'll be late.

我给妈妈打个电话告诉她我们要迟到了。

youdao

I got closer and smiled to let her know that I was there to talk, to help.

我走近她，朝她微笑着，让她知道需要聊天和帮忙的时候我都在。

youdao

If she helped you set up an interview, let her know how it went.

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She called the other twin -- their daughter Julie -- to let her know the news.

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After my first miscarriage, my husband called my manager and let her know what was going on.

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