Here are a few options for a description for the WordPress post tag “有用 (Yǒuyòng)” in Traditional Chinese, ranging in style and brevity:

**Option 1: Concise and Descriptive**

> 標記與標示「有用」資訊的標籤。用於文章內容傳達實用性、價值與助益。旨在讓讀者快速辨識有幫助、值得參考的主題。
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> (Biao ji yu biao shi “Yǒuyòng” zīxùn de biāoqiān. Yòngyú wénzhāng nèiróng chuándá shíyòngxìng, jiàzhí yǔ zhùyì. Zhǐzài ràng dúzhě kuàisù biànshì yǒu bāngzhù, zhídé cānkǎo de zhǔtí.)
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> Translation: A tag marking and indicating “useful” information. Used for article content that conveys practicality, value, and benefit. Aims to help readers quickly identify helpful and referable topics.

**Option 2: Focus on Benefits**

> 尋找實用、有用的文章嗎？此標籤專為標記提供實際價值與幫助的內容。輕鬆找到對您有益的資訊，解決問題，提升生活！
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> (Xúnzhǎo shíyòng, yǒuyòng de wénzhāng ma? Cǐ biāoqiān zhuān wèi biāojì tígōng shíjì jiàzhí yǔ bāngzhù de nèiróng. Qīngsōng zhǎodào duì nín yǒuyì de zīxùn, jiějué wèntí, tíshēng shēnghuó!)
>
> Translation: Looking for practical and useful articles? This tag is dedicated to marking content that provides practical value and help. Easily find information that benefits you, solves problems, and improves your life!

**Option 3: Simple & Direct**

> 標記代表實用、對您有幫助的文章。
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> (Biāo jì dàibiǎo shíyòng, duì nín yǒu bāngzhù de wénzhāng.)
>
> Translation: A tag representing practical and helpful articles for you.

**Option 4: Slightly More Sophisticated**

> 這個標籤用於標示那些能為您提供實際助益、帶來價值與啟發的內容。 讓您更容易找到解決方案，或者在您的人生旅途上獲得一些提示。
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> (Zhège biāoqiān yòngyú biāoshì nàxiē néng wèi nín tígōng shí jì zhùyì, dài lái jiàzhí yǔ qǐfā de nèiróng. Ràng nín gèng róngyì zhǎodào jiějué fāng’àn, huòzhě zài nín de rénshēng lǚtú shang huòdé yīxiē tíshì.)
>
> Translation: This tag is used to mark content that can provide you with practical benefits, bring value, and offer inspiration. It makes it easier for you to find solutions or obtain some hints on your life’s journey.

**Which option is best depends on:**

* **The overall tone of your website:** Is it formal, informal, academic, etc.?
* **The length of the description you want:** Some options are much shorter than others.
* **The target audience:** Who are you trying to reach?

I recommend choosing the option that best fits your needs. Remember to consider the Chinese character limit for your WordPress tag descriptions! You can often shorten them further if necessary. Good luck!