The waitress had a sweet smile, one that even being on her feet for an entire day couldn't erase.請問這ㄧ句的句型結構是什麼?為什麼要這樣寫? 問題是that even being.?

1. <One that ... couldn't erase> 是 <a sweet smile> 的同位語 是拿來當 had的受詞.
2. 為什麼要這樣寫? 問題是that even being.?
不然要怎寫啊?醬子寫超自然的耶!

3. that even being ... couldn't erase. 裡面的that是關係代名詞.是用來代表前面的one.
that ... couldn't erase = 無法(讓...)抹去的 東東 (微笑)

4. 整句的意思是:

那位女恃有 "一天辛勞都無法抹去的" 笑容.