现在“ciao”是用于非正式场合的问候语，但它的本意“仆人“，可追溯到古时“我是你的仆人”这一用法，与“我是你卑微的仆人”在书信署名里传达的敬意一致。

Now the word “ciao” is casual, but its meaning “slave, ” harkens back to “I am your slave, ” the same sense of respect a person signing off with “your humble servant” tried to convey.

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这些问候语既可以用在正式的场合中，也可以用在非正式的场合中。

These greetings can be used in both formal and informal situations and are simply a friendly and common way to greet both friends and people you meet for the first time.

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