Here are a few options for the description, playing with different tones and emphasizing different aspects of the tag:

**Option 1: Concise and Descriptive**

* **Traditional Chinese:** 引擎排量為4000立方厘米。 (Yǐnqíng páiliàng wèi 4000 lìfāng límǐ.)
* **English Translation:** Engine displacement of 4000 cubic centimeters.
* **Tone:** Neutral, factual. Suitable for technical content or lists.

**Option 2: Emphasizing the Power/Performance**

* **Traditional Chinese:** 4000cc引擎，強勁動力，極致體驗! (4000cc yǐnqíng, qiángjìng dònglì, jízhi tǐyàn!)
* **English Translation:** 4000cc engine, powerful performance, ultimate experience!
* **Tone:** Enthusiastic, highlights performance. Suitable for car reviews, discussions about engines.

**Option 3: Broader Definition (Good for general use)**

* **Traditional Chinese:** 標記有關4000立方厘米排量的內容，涵蓋各種領域。(Biāojì yǒuguān 4000 lìfāng límǐ páiliàng de nèiróng, hánggài gèzhǒng lǐngyù.)
* **English Translation:** Tag related to content with a 4000 cubic centimeter displacement, covering various fields.
* **Tone:** General, useful if the tag is applied broadly. Useful if you’re covering different topics.

**Option 4: More specific to a general audience (car-related)**

* **Traditional Chinese:** 4000cc 車輛，性能優越，駕駛樂趣無限。 (4000cc chēliàng, xìngnéng yōuyuè, jiàshǐ lèqù wúxiàn.)
* **English Translation:** 4000cc vehicles, superior performance, endless driving pleasure.
* **Tone:** Enthusiastic, focused on driving experience.

**How to choose the best option:**

* **Consider the content you are tagging:** What kind of articles or posts will be using this tag?
* **Think about your audience:** Are they technical experts or general enthusiasts?
* **Keep it concise:** WordPress tag descriptions are often displayed alongside the tag, so a short description is best.
* **Be consistent:** If you are using other tags for engine size, maintain the same writing style.

**Where to put the description in WordPress:**

1. **Go to Posts > Tags in your WordPress admin panel.**
2. **Find the “4000cc” tag and click “Edit.”**
3. **Look for the “Description” field.** This is where you paste your chosen Traditional Chinese description.

Remember to save or update the tag after adding the description.