airs and graces idiom
装腔作势，摆架子;矫揉造作
false ways of behaving that are intended to make other people feel that you are important and belong to a high social class
He was always putting on airs and graces. 他总是装腔作势，故作姿态。
She's got no reason to give herself airs and graces. 她没有理由摆架子。