在英语中有很多问候的方式可以用在正式和非正式的场合里。

There are lots of ways of greeting in English which can be used in both formal and informal situations, eg: How are you doing?

youdao

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.

youdao

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.

youdao