A：這個 as 是當 (準) 關係代名詞用。要特別注意的是，這個 as 千萬不可用 that 來代替，否則意思就不一樣了，因為 “such + 名詞片語 + that” 是在表示「因果」(cause and effect) 的關係，而 that 所引導的是結果子句；茲舉一例來說明之：
- This book is written in such easy English as beginners can understand. (這本書是以初學者所能理解的簡易英文寫成的 — as 為關係代名詞)
- This book is written in such easy English that beginners can understand it. (這本書是以簡易的英文寫成，所以初學者都能瞭解 — that 為附屬連接詞)
所以，像 Such honesty that he showed is rare in a politician nowadays. (他所展現的這種誠實作風在現今的政治人物中純屬希罕) 這樣的句子是錯誤的，其中 that 應改為 as。
另外，”the same… as” 若其後接子句，這個 as 也是當關係代名詞用，不過我們可以用 that 來代替它。例如 (下面兩句的結構和意思完全相同，亦即 that 也是關係代名詞)：
- Could I have the same room as I had last time? (我可以住我上次住過的那個房間?)
- Could I have the same room that I had last time?