考点一 分类及主要引导词

　　1. 时间状语从句

　　主要引导词：when, whenever, before, after, until, while, since, once, so long as, as soon as, the moment, every time, as, next time

　　I will call you after I get to the company.

　　I don't call her until I get to the company.

　　Every time I feel lonely, she comes to talk to me.

　　2. 地点状语从句

　　主要引导词：where, wherever

　　Wherever you go, I will be right here waiting for you.

　　3. 原因状语从句

　　主要引导词：because, as, since, considering that, now that, not that, seeing that

　　注意：in that是书面语中原因状语从句的引导词，相当于because, 在填空题中曾经出现

　　Now that it is raining, we'd better cancal the meeting.

　　4. 目的状语从句

　　主要引导词：so that, in order that, for fear that, in case, lest

　　5. 结果状语从句

　　主要引导词：so…that, so that, such…that

　　注意：so…that句式和too…to句式的区别是重要考点之一，so…that接从句；too…to接不定式

　　The old lady is so generous that a lot of people admire her.

　　She is too young to resist it.

　　6. 条件状语从句

　　主要引导词：if, unless, in case, so long as, on condition (that), provided (that)

　　7. 让步状语从句

　　主要引导词：though, although, no matter, even if, even though, however, whatever

　　注意though, although等都不能够与but连用

　　例题：

　　(1)

　　Anthropology is a science ----anthropologists use a rigorous set of methods and techniques to document observations that can be checked by others.

　　(A) in that

　　(B) that in

　　(C) that

　　(D) in

　　答案：A

　　解释：空白处前后均是完整的主谓句, 意思上后者是对前者的解释说明, 推知需填入从句引导词, in that是一特殊的状语从句引导词, 表示原因, 与此句意思吻合

　　(2)

　　Gorillas are quiet animals, ----they are able to make about twenty different sounds.

　　(A) how

　　(B) in spite of

　　(C) because of

　　(D) even though

　　答案：D

　　解释：空白前后都是完整的主谓句，需填的一定是连词，可首先排除BC,A引导的宾语从句不能接在表语后，只有D正确，构成状语从句

　　考点二 状语从句中的省略

　　部分状语从句可以省略，在填空题中时有出现

　　如：Although defeated, he did not lose heart. (从句中省略了he was)

　　If informed timely, I wouldn't have missed the meeting. (从句中省略了I were)

　　例题：

　　(1)

　　----relatively costly, the diesel engine is highly efficient and needs servicing infrequently

　　(A) Even

　　(B) It is

　　(C) Even though

　　(D) There is

　　答案：C

　　解释：逗号后是完整的句子, 缺少的可能是从句或状语的一部分, B、D是主谓结构, 肯定不对; A 是副词, 为甚至之意, 放在原句中讲不通; C 是尽管的意思, 实际上省略了状语从句的主谓语it is, 符合题意. 还需注意的是costly是形容词而不是副词

　　(2)

　　Although ---- rigid, bones exhibit a degree of elasticity that enables the skeleton to withstand considerable impact.

　　(A) apparently

　　(B) are apparently

　　(C) apparently their

　　(D) are they apparently

　　答案：A

　　解释：although是让步状语从句引导词，空格处需要从句的主谓语，B缺少主语，D不应倒装，可先排除；their不能修饰形容词rigid，B也可排除；A是从句的省略式，相当于Although they are apparently rigid