狀語從句在主從復合句中修飾主句中的動詞、形容詞或副詞等，按意義可以分為時間、地點、原因、目的、結果、條件、方式、比較、讓步等狀語從句。
六.讓步狀語從句。
1.由however, whatever, whenever, whoever等引導，相當于no matter how/what/when/who 等。例如：
We’ll have to finish the job,_____. (NMET99)
A. long it takes however B. it takes however long
C. long however it takes D. however long it takes
答案： D. however 是副詞性引導詞，必須直接位于所修飾的形容詞long之前，并放在句首引導狀語從句。
應該注意：however, whatever, whenever, wherever 等還可以引導名詞性從句，而no matter how, no matter what, no matter when, no matter where等只能引導狀語從句。例如：
Whatever I said couldn’t cause his interest in the topic.
2.由though, although, as, even though/if 等引導讓步狀語從句，不能與 but 連用，但可于yet連用。
(1).由as引導的讓步狀語從句，必須倒裝表語形容詞、名詞(前面不用冠詞)或者副詞狀語或者動詞原形，though 引導的讓步狀語從句可以倒裝，也可以不倒裝，而although引導的不能倒裝。例如：
He didn’t light the fire though/although it was cold.
Although he is very old, (yet) he still jogs every day.
Rich as/though he is(=Although he is rich), I don’t envy him.
Difficult that task was, they managed to finish it in time.
Child as he is, he knows a lot.
Much as I love it, I’ll not buy it.
Try as they may, they won’t succeed.
(2).even if, even though 表示“即使，縱然”，有退一步設想的意味，多用于書面語中。
例如：
I’ll do it, even if it takes me all the afternoon.
Even if he did say so, we can not be sure that he was telling the truth.
(3).whether(…or)引導讓步狀語從句,提供兩個或兩個以上供選擇的條件。注意此時的whether不能換成if. 例如：
Whether he drives or (whether he) takes the train, he’ll be there on time.
七.條件狀語從句
條件狀語從句用if, unless, as/so long as, on condition that, provided, providing, now that, in that 等引導。除了應注意這些詞的語義差別之外，還需注意，在條件狀語從句中不能用將來時，只能用一般現在時表示一般將來時。例如：
If China becomes strong and powerful, we’ll never bully other countries.
As long as we don’t lose heart, we’ll turn our dreams into realities.
He won’t believe anything unless he sees it with his own eyes.
I will lend you the money on condition that you pay it back in one month.
有時if 條件句中也用will, 但此時用來表示主語的意愿。例如：
If you will come to work in our city, I’ll try my best to meet your demands.(如果你愿意來我市工作，我將盡力滿足你的要求。)
八.方式狀語從句
1.方式狀語從句用 as, just as, as if, as though 引導。
2.關于方式狀語從句值得注意兩點：
(1).as 表示行為方式;
(2).在打比方與事實相反或不可能實現時，as if /though 引導的從句用虛擬語氣。但當句子謂語為過去時態時，特別是當句子謂語為look, seem, taste, smell等感官動詞時，從句謂語動詞不用虛擬語氣。例如：
I have changed the plan as you suggested.
When at Rome do as the Romans do.(入鄉隨俗)
I have loved you as if you were my own son.
It looks as if it is going to rain.
九.比較狀語從句
比較狀語從句常由than, as…as , not so/as…as, the more…, the more …等引導。例如：
He didn’t do as much as he had promised.
I know you as well as any member of your family.
Now we can produce much more steel than Japan.
The longer you stay with him, the better you will know him.
