brass neck
noun [ S or U ] UK informal disapproving uk/ˌbrɑːs ˈnek/ us/ˌbræs ˈnek/
厚脸皮
a type of behaviour where someone is extremely confident about their own actions but does not understand that their behaviour is unacceptable to others
She's got a brass neck to ask for a day off when we're so busy. 我们这么忙，她还腆着脸要求说要休假一天。