When [While] in trouble, ask her for help.

遇到麻烦的时候你就去找她帮忙。

youdao

Were she my friend, I would ask her for help.

如果她是我的朋友，我就会请她帮忙。

youdao

I do not know her well enough to ask her for help.

我对她不够熟悉不好求她帮忙。

youdao

I went to Madame Vulpes to ask her for help with a scientific problem.

VOA: special.2009.07.18

It was weeks before her death that Amy did summon up the courage to ask her family for help and begin the process of removing Morrison from her life.

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She trained me in advance to cover for her, made sure I knew who to ask for help and didn't penalize me for any mistakes I made while she was away.

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She took her toddler sons to a nearby house to ask for help.

FORBES: Mayor Michael Bloomberg, Superstorm Sandy, and Social Media: A New York City Perspective