play-acting
noun [ U ] uk/ˈpleɪ.æk.tɪŋ/ us/ˈpleɪ.æk.t̬ɪŋ/
假装;演戏
an attempt to hide your feelings from other people, or to entertain them, by deliberately behaving in a way that does not represent your true feelings
Don't take any notice of him - it's just play-acting. 不要管他——他是在装腔作势。