Under the sea教案
(5) n (c) “目擊者，證人”常與to連用the police found the witness to the murder case.he was a witness to the accident.
(6) n (c,u) 證詞，證據，證明 his ragged clothes were (a) witness to his poverty.
the old man gave witness on behalf of an accused person. 那位老人為被告作證。 on behalf of 代表/替…
相關短語：be a witness to 是…的目擊者 give witness on behalf of 替…作證 witness to 為某事作證說
4 as (1) conj 用作連詞可引導時間，原因，讓步，比較，方式等狀語從句
as he looked at her, she made a face. as he didn’t know much english, he got out his dictionary and looked up .
he doesn’t speak as the other people do . you must do as i told you. he is not so diligent as you.
young as he is , he knows a lot. child/student as he is, he has a good knowledge of history.
as a young boy , he lost his parents in the war. i watched her as she combed her hair.
i have changed it as you suggested. i read the letter as i walked along the river.
as you weren’t there , i left a message. as he has been ill , perhaps he needs help.
try as he would , he couldn’t open the door. tired as they were, they walked on. leave the table as it is.
(2) 作關系代詞，引導限制性定語從句，先行詞前常有such, the same, as, so 與之呼應，構成such…as, so…as,等
we’ll make such computers as are needed in different branches of science.
i want to buy the same shoes as were advertised.
(3) 作關系代詞，引導非限制性定語從句，as 指前或后面整個句子的內容。
as you can see in the map, the two cities are far away from each other.
as everybody knows ,all that glitters is not gold. as is known to us all, Chinese Taiwan is part of china.
(4) prep 作為 you will be welcomed as a hero tomorrow morning . she treats him as her brother.
近義詞辨析：① as 強調主從句謂語動詞的動作同時發生。 we talked as we walked on our way home.
②when 側重表示瞬間（時間點）,主從句所述動作可以同時也可先后發生 .
he went home when he had finished his homework.(先后) it was snowing when we got to the airport. （同時）
③while 表示時間段或兩個延續性動作同時發生strike while the iron is hot. please look after her while i’m away.
④because 語氣最強，著重說明原因或理由（其從句一般放在主句之后）， 在回答why問句時，必須用because 不能用其他詞。 he was tired because he had done much hard work.
⑤since 語氣比because 稍弱，表示關系上的必然結果，一般譯成“既然，鑒于” （一般放在主句前）