HSK 7–9 · Practice
画蛇添足
to ruin something by adding unnecessary details; to overdo it
文章已经很完整，再加一段就画蛇添足了。
Wénzhāng yǐjīng hěn wánzhěng， zài jiā yí duàn jiù huàshé-tiānzúle。
The article is already complete; adding another paragraph would be overdoing it.