一、as引導讓步狀語從句
1、名詞 + as / though + 主語 + 動詞
king as he was，he was unhappy. 他雖是國王，但他並不幸福。
child as he is，he knows to help other. 他雖是個孩子，卻知道幫助別人。
【說明】其中的動詞通常為連繫動詞，也就是說位於句首的名詞是其後連系動詞的表語。另外，要特別注意位於句首的名詞前習慣上不用冠詞，即使其前有形容詞修飾也不用冠詞。比較：
boy as ［though］ he is， he likes to play with girls.=though he is a boy，he likes to play with girls. 他雖是男孩，卻喜歡與女孩子玩。
strong man as ［though］ he is，general botha has been severely put to the test during the past few weeks.= though he is a strong man， general botha has been severely put to the test during the past few weeks. 波賽將軍雖然堅強，但在過去的數週裡也受到了嚴峻的考驗。
2、形容詞 + as / though + 主語 + 動詞
successful as he is，he is not proud. 他雖然成功，但不驕傲。
improbable as it seems，it』s true. 雖然看起來不太可能，但卻是真的。
stupid as it sounds，i was so in love with her that i believed her. 儘管聽起來很愚蠢，我是如此愛她竟然相信了她的話。
patient as he was，he didn』t like waiting that long. 他雖說有耐心，也不願等這麼長。
beautiful though the necklace was，we thought it was over-priced. 那條項鍊雖然很漂亮，我們認為價錢太高。
【說明】其中的動詞也通常為連繫動詞，也就是說位於句首的形容詞是其後連系動詞的表語。
3、副詞 + as / though + 主語 + 動詞
much as i like paris，i couldn』t live there. 儘管我喜歡巴黎，但我不能住在那裡。
hard though they tried，they couldn』t make her change her mind. 儘管他們做了很大努力，卻沒法讓她改變主意。
fast as you read， you can』t finish the book in two days. 儘管你讀得很快，你總不能在兩天之內就讀完這本書。
he was unable to make much progress，hard as he tried. 儘管他做了努力，卻未能取得很大進步。
【說明】有的詞典將 much as 作為習語看待，認為它是乙個用以引導讓步狀語從句的復合連詞。再如：
much as i admire him as a writer，i do not like him as a man. 他作為一名作家我很佩服他，但我卻不喜歡他這個人。
much as i like you，i couldn』t live with you. 我儘管很喜歡你，卻不能和你在一起生活。
4、動詞原形 + as / though + 主語 + 動詞
object as you may，i』ll go.縱使你反對，我也要去。
try as he might，he couldn』t solve the problem. 儘管他想方設法，卻未解決這個問題。
search as they would，they would find nobody in the house. 無論怎樣搜查，他們在房子裡仍然沒有找到乙個人。
dislike him as we may，we must acknowledge his greatness. 儘管我們不喜歡他，但必須承認他的偉大。
lose money as i did，we got a lot of experience. 錢雖然丟了，我們卻得到了許多經驗。
fail in the election as he did，he became famous for his fiery speech against sl**ery. 儘管落選了，但他卻以其反對奴隸制的激烈演說而出了名。
【說明】主語後的動詞通常為 may，might，would，did 等情態動詞或助動詞(若表示情態意義，則選用情態動詞；若陳述事實，則用 did，do 等助動詞)。
5、分詞 + as / though + 主語 + 動詞
raining hard as it is， i』m going out for a walk. 雖然正在下著大雨，我還是要出去散步。
surrounded as we were by the enemy，we managed to march forward. 雖然我們被敵人包圍著，但我們還是設法前進了。
munching the apple as he was，he had got an eye for all john』s movements. 他儘管在乙個勁地嚼著蘋果，但仍警惕著約翰的一舉一動。
6、補充說明
1）這類倒裝的讓步狀語從句可用 as， though 來引導，不能用 although 來引導；但是，未倒裝的讓步狀語從句卻可用 though， although 來引導，而不能用 as 來引導。也就是說， although 引導讓步狀語從句時不能倒裝，as 引導讓步狀語從句時必須倒裝，而 though 引導讓步狀語從句時可以倒裝也可以不倒裝。如：
雖然很晚了，但我們還是繼續工作。
正：late as ［though］ it was，we still went on working.
正：though it was late，we still went on working.
誤：late although it was，we still went on working .
誤：as it was late，we still went on working.
2）上面提到的倒裝結構有時也可用來表示原因，區別的辦法主要看句子的內容：讓步從句的內容大多數與主句在意義上相反，而原因從句則與主句之間有因果關係。比較：
tired as he was，he sat up late studying at night. 昨晚他雖然很疲倦了，但還是學習到很晚才睡。(表讓步)
tired as he was，he went to bed early. 因為很累，所以他睡得很早。(表原因)
young as he was，he was equal to the task. 他雖年輕，卻能勝任這項工作。(表讓步)
young as he was，he was not equal to the task. 他因為年輕，所以不能勝任這項工作。(表原因)
3）在美國英語中，人們通常用 as...as 引導讓步狀語從句。如：
cold as it was， we went out.=as cold as it was， we went out. 儘管天氣冷，我們還是出去了。
successful as he is， he is not proud.=as successful as he is， he is not proud. 他雖成功了，但不驕傲。
二、as 引導定語從句
as 的用法:(as 引導定語從句, 在定語從句中作主語、賓語、表語)
(一) 如為限制性的，多用於the same …as ; the same as；such …as …; as many/much as；so …as等結構中。如：
1. i h**e the same book as you (h**e). 我有一本和你的一樣的書。
her attitude to him was quite the same as it had always been. (關係代詞as和指示代詞same連用, 在從句中用作表語, 先行詞是same.)
2.---why didn't you mention that in face of the police just now?
--- i thought it was such a minor detail as was hardly worth mentioning.
we will only discuss such problems as h**e something to do with our own interests.
don't do such things as you are not sure about.
there is no such place as you dream of in all this world.
比較：i live in the same house that he used to live in.
i'm wearing the same shirt as you wore yesterday.
比較：here is so big a stone as no one can lift. （定語從句）
here is so big a stone that no one can lift it.（結果狀語從句）
(二) 如為非限制性的，多單獨引導乙個定語從句，這種定語從句可置於句首，句中或句尾，譯為"正如，這一點"。（動詞常為know, see, expect, point out, etc.）
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