谦恭

She is a scholar of modesty and courtesy.

He spoke in a mild and respectful tone.

be modest in speech and courteous in behaviour

courteous in wording

practise humility

be respectful and polite

be modest and respectful

be modest and honest

be modest and willing to learn

humble attitude

humbly apologize (to sb for sth); make a humble apology

learn to be modest and courteous