Míngzhī bùduì, yě bù tóng tāmen zuò yuánzé shàng de zhēnglùn, rèn qí xiàqù, qiú dé hépíng hé qīnrè. Huòzhě qīngmiáodànxiě de shuō yī dùn, bù zuò chèdǐ jiějué, bǎochíyītuánhéqì.[Pinyin]
To let things slide for the sake of peace and friendship when a person has clearly gone wrong, and refrain from principled argument. Or to touch on the matter lightly instead of going into it thoroughly, so as tokeep on good terms.