Height and Weight examples in module 3 are a bit awkward

Didn't particularly enjoy explaining this code, defining bodily adjectives by means of weight and height made me feel like I was walking on eggshels. I'll come up with a different example unless anyone else beats me to it.

先找到 Module 3 的課程教材，並檢視 issue 中描述的身高與體重範例。將該範例替換為更舒適的替代方案，同時保留課程原本 intended 的解釋，然後確認周圍教材仍然連貫。

由索引模型根據 Issue 內容生成。