Here are a few options for the description of the WordPress post tag “遊輪大小” (Cruise Ship Size) in Traditional Chinese, ranging in formality and clarity:

**Option 1 (Concise & Clear):**

> 了解遊輪的尺寸，包括噸位、長度、寬度等。

* **Translation:** Understand the size of cruise ships, including tonnage, length, width, etc.

* **Why it’s good:** Direct, easy to understand, and covers the key aspects of size.

**Option 2 (Slightly More Detailed):**

> 探索遊輪大小的不同指標，如噸位（衡量船隻體積）、長度、寬度和吃水深度，幫助您更好地選擇適合您的遊輪。

* **Translation:** Explore the different indicators of cruise ship size, such as tonnage (measuring ship volume), length, width, and draft, to help you better choose the cruise ship that suits you.

* **Why it’s good:** Provides more context by explaining the meaning of tonnage and also mentions draft, a helpful indicator.

**Option 3 (Focus on Practicality):**

> 想知道遊輪有多大？這裡介紹遊輪大小的各種衡量方式，包括噸位、尺寸等，幫助您在規劃行程時，做出更明智的選擇。

* **Translation:** Want to know how big a cruise ship is? Here we introduce various ways of measuring cruise ship size, including tonnage, dimensions, etc., to help you make a more informed choice when planning your trip.

* **Why it’s good:** Emphasizes the practical benefit of understanding size for trip planning.

**Option 4 (More Conversational):**

> 遊輪的大小究竟是怎麼算的？這裡解釋遊輪的噸位、長度、寬度，讓你對遊輪的尺寸有個初步的了解，方便你選擇適合的郵輪假期！

* **Translation:** How is the size of a cruise ship actually calculated? Here we explain the tonnage, length, and width of cruise ships, giving you a basic understanding of their dimensions, and making it easier to choose the right cruise holiday for you!

* **Why it’s good:** More engaging and uses common questions to pique interest. Includes the word “郵輪” which is a common word.

**How to choose the best option:**

* **Consider your audience:** Are they beginners or experienced cruisers?
* **Consider the content:** Does the tag cover only basic information, or more detailed discussions?
* **Keep it concise:** WordPress tags are best when they are relatively short and to the point.

I recommend choosing either **Option 1** or **Option 2** for most situations. They provide a good balance of clarity and completeness. Remember to choose the one that best reflects the content you will be tagging!