How do you use 画蛇添足 in a sentence?
The poster looked great already, but adding five more glitter stars was drawing legs on a snake.
海报本来已经很好看了，再加五颗亮粉星星就是画蛇添足。
Her speech was clear and powerful, but the extra long joke at the end ruined it by drawing legs on a snake.
她的演讲本来清楚又有力，但最后加上的那个冗长笑话反而成了画蛇添足。
Dad fixed the bike perfectly, and checking every screw again for an hour felt like drawing legs on a snake.
爸爸已经把自行车修好了，还花一个小时反复检查每颗螺丝，感觉有点画蛇添足。
When does it fit — and when doesn't it?
✓ Fits
The cake was beautifully decorated, but adding three kinds of candy on top was drawing legs on a snake.
蛋糕本来装饰得很漂亮，再放上三种糖果就是画蛇添足了。
✗ Doesn't fit
He forgot to bring his homework, so this was drawing legs on a snake.
他忘了带作业，所以这就是画蛇添足。
Why?
The idiom only works when someone adds something unnecessary to an already finished or good thing, not when they simply forget something.
这个成语只适用于在已经完成或已经很好的事物上多此一举地添加内容，不适用于单纯忘记带东西的情况。
Common mistake
Using the idiom for any mistake or failure, even when nothing extra was added.
把这个成语用来表示任何错误或失败，即使根本没有多加东西。
Correction
Use it only when a person unnecessarily adds more and makes the result worse.
这个成语要用在一个人多此一举、额外添加内容，结果反而把事情弄糟的时候。
Why does this error happen?
This error happens because learners remember the idea of a bad result but forget that the key point is unnecessary addition.
What do exams test about this idiom?
In PSLE or HSK questions, this idiom is usually tested for whether students understand that it describes unnecessary extra action that spoils something already complete.
小测验 · Quick Quiz
Test your understanding
1. What does 画蛇添足 mean?
画蛇添足是什么意思？
To ruin something already done well by adding unnecessary extras
在已经完成的事情上多余添加，反而把它弄糟了
To rush a task and make careless mistakes along the way
急于完成任务，沿途犯下粗心的错误
To copy someone else's idea without contributing anything original
照搬别人的想法，没有任何原创贡献
2. What did A-Sheng keep doing after his snake drawing was already finished?
阿盛画完蛇之后，一直在做什么？
He coloured it in with bright paints
他用鲜艳的颜色涂了上去
He ran to show it to the judges
他跑去把画给裁判看
He kept adding more and more legs to it
他一直不停地给蛇加腿
3. Which sentence uses 画蛇添足 correctly?
哪个句子正确地使用了画蛇添足？
The cake was beautifully decorated, but piling three kinds of candy on top was drawing legs on a snake.
蛋糕装饰得已经很漂亮了，却又堆上三种糖果，真是画蛇添足。
He forgot to bring his homework — that was drawing legs on a snake.
他忘了带作业——这就是画蛇添足。
She worked hard and delivered a great speech — that was drawing legs on a snake.
她努力准备，发表了一篇精彩的演讲——这就是画蛇添足。
Answers: 1A · 2C · 3A