驴唇不对马嘴

incongruous, irrelevant

lǘ chún bù duì mǎ zuǐ ㄌㄩˊ ㄔㄨㄣˊ ㄅㄨˊ ㄉㄨㄟˋ ㄇㄚˇ ㄗㄨㄟˇ