As to use occasions, ordinary people or those discommodious to greet directly can be called "teachers".

在使用场合方面，对不方便称呼的人和普通人都可以称为“老师”。

youdao

I only use that on special occasions, so it's as good as new.

我只在特殊场合用，所以它完好如新。

《柯林斯英汉双解大词典》

In the absence of good documentation, I have, on a number of occasions, tried to use modern online help systems to troubleshoot problems.

在许多场合缺少好的文档，这时我会试着使用现代的在线帮助系统检查问题。

youdao

She has one of those lightweight portable wheelchairs to use for these occasions and it really helped.

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Whatever individual discretion they use on some occasions they follow the crowd as if that was the only discretionary power they had.

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Room attendants told us they felt they had no other option but to use the bathroom towels on occasions.

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