Here are a few options for the description of a WordPress post tag with the title “選填科系” (Choose Department/Major) in Traditional Chinese, each with a slightly different nuance:

**Option 1 (General & Straightforward):**

> 關於大學或研究所申請中，學生選擇科系、填寫志願的相關資訊。涵蓋科系介紹、選擇技巧、申請流程等。 (Guān yú dàxué huò yánjiūsuǒ shēnqǐng zhōng, xuéshēng xuǎnzé kēxì, tiánxiě zhìyuàn de xiāngguān zīxùn. Hánguài kēxì jièshào, xuǎnzé jìqiǎo, shēnqǐng liúchéng děng.)
>
> *Translation: Information related to students choosing departments/majors and filling out application choices in university or graduate school applications. Covers department introductions, selection techniques, application processes, etc.*

**Option 2 (Focus on Advice and Tips):**

> 提供給學生選填科系時的建議、訣竅和實用指南。幫助你了解不同科系的特點，做出最適合自己的選擇。 (Tígōng gěi xuéshēng xuǎntían kēxì shí de jiànyì, juéqiào hé shíyòng zhǐnán. Bāngzhù nǐ liǎojiě bùtóng kēxì de tèdiǎn, zuòchū zuì shìhé zìjǐ de xuǎnzé.)
>
> *Translation: Provides suggestions, tips, and practical guides for students choosing departments. Helps you understand the characteristics of different departments and make the choice that’s best for you.*

**Option 3 (Emphasis on Exploration and Information):**

> 一站式收集科系資料，助你探索、了解不同學科與領域。包括科系介紹、未來出路、升學考試數據等，協助學生做出明智的科系選擇。 (Yī zhànshì shōují kēxì zīliào, zhù nǐ tànsuǒ, liǎojiě bùtóng xuékē yǔ lǐngyù. Bāokuò kēxì jièshào, wèilái chūlù, shēngxué kǎoshì shùjù děng, xiézhù xuéshēng zuòchū míngzhì de kēxì xuǎnzé.)
>
> *Translation: A one-stop shop for collecting department information to help you explore and understand different disciplines and fields. Includes department introductions, career paths, university entrance exam data, etc., to assist students in making informed department choices.*

**Option 4 (Concise and broad):**

> 關於升學申請中，科系選擇的資訊與建議。 (Guān yú shēngxué shēnqǐng zhōng, kēxì xuǎnzé de zīxùn yǔ jiànyì.)
>
> *Translation: Information and advice on choosing departments during university application.*

**Choosing the best option:**

* **Consider your target audience:** Are you focusing on students, parents, or both?
* **Match the content:** Does your blog cover a broad range of topics about choosing a major, or does it focus on specific aspects?
* **Keep it short and clear:** WordPress tag descriptions should be concise.

I recommend **Option 1** or **Option 2** as they provide a good balance of information and potential topics. If you have a very specific focus, adjust the description accordingly.