基本上這些算文法的東西，我的文法底子一向不佳，敬請指正
as→
主要用於ProN-REL(由於使用場合的限制，常稱準關代 )、
CONj(又分為相關連接詞與附屬連接詞 )、
Prep(介係詞)、
Adv (副詞，略，主要考點為前三項 )
as (ProN-REL, 關係代名詞) = that, who, which (OG 132、187)
場合限制：used after as、same、such；即as...as、the same...as、such as
例句
You shall have as much money(n) as you need. (關係子句 as you need是形容詞子句，修飾其先行詞 money，as在其引領的子句裏是做 need的受詞。關係代名詞為什麼不用which?因為as之後的關係代名詞不可用which)
She is such a girl(n) as I like. (as為i like的受詞)
You like the same color(n) as she does (as 為she does的受詞)
as (Correlative Conjunctions, 相關連接詞)，用於as...as結構
usually used as a correlative after an adjective or adverb modified by adverbial as or so
Jane is as cute(adj) as Sarah (is).
John runs as fast(adv) as his sport teacher (does).
Being a mother is not as bad(adj) as I thought at first.
Tom goes to the church as frequently(adv) as he goes to the theater.(改分詞即為going to the theater)
小結：同樣是as...as的場合，第二個as可以做為關代或是連接詞，判斷的訣竅在於它是跟隨在N之後，還是跟隨在adj/adv之後
as (Subordinate Conjunctions, 從屬連接詞)，用於連接主要子句與附屬子句之用
結構為As + S2 + V2..., S1 + V1...
句意包括如同(本句意常拿來配like成為考點)，正當(when)，因為(because, OG 184)，
相關連接詞與從屬連接詞，文法上沒有不同，修辭功能有差異，比較比較......
as (prep) 是表示狀態／身份 (og 97、235)
例句
He has worked as a diplomat in Taiwan.
Mr. Wang is regarded as one of the most successful businessmen in 21st century.
表身份時用as，Prep的有將其放到「句首」的趨勢（如果選項中又有同位語，就還蠻混淆的）PP1-159&160
表示狀態：
if you do something as a child or as a teenager, for example, you do it when you are a child or a teenager. (OG 69)
The news came as a complete surprise.
