SAT 语法题！！ 5
A. is because adults are getting fewer cavities and becoming more vain
D. is occuring because adults are getting fewer cavities and becoming more vain
答案D 这题始终不明白
2.(a squadron of newly trained, enthusiastic firefighters from training academies,each year they graduate )to begin work in the nation's cities.
答案 Each year a squadron of newly trained, enthusiastic firefighters graduates from training academies.
（为什么原句中A SQUADRON OF.... 不能修饰后句的THEY？另外就算修饰，THEY要改成HE OR SHE吗？）
3. (If there had been) a power failure, the hospital will run on electricity from its own generators, which can operate for 200 hours.
答案D Should there be
（是不是后面是对将来的情况，前句也要是对未来的虚拟？这种情况是否也使用于过去或者现在？）
（By painting them） this afternoon, the walls would be completely dry by tomorrow evening.
答案(C) Were they to be painted
就像这题么
4.（There is speculation that the name "Wendy" was） the invention of J.M Barrie,who created a character by that name for his famous play Peter Pan.
E) The name "Wendy" is by some speculation the invention of Barrie
答案是原句，为什么 展开
5. Early rock and roll music, like jazz and the blues, celebrated characteristics of urban life that (was once) only disparaged: loud, repetitive city sounds were reproduced as raucous melodies and insistent rhythms
【解读】
通过句子分析判断，分析时可以剔出必要的附加成分（方括号标出）。
主句：Early rock and roll music, 【like jazz and the blues,】celebrated characteristics of urban life 早期的摇滚乐【如爵士乐和布鲁斯】表现出了城市生活的特点
定语从句：that (was once) 【only】 disparaged: 反而一度被贬低的…：
从冒号后loud, repetitive city sounds were reproduced (喧嚣且重复的城市声音被复制出来) 【as raucous melodies and insistent rhythms (作为沙哑悦耳并动人的旋律)】的解释，特别是reproduce（再生/翻版/重现）的含义，可知，定语从句的关系代词指代rock and roll music。
6. (A significant factor) to include in the budget when (buying) a car are the costs of fuel and maintenance and the insurance payments.
【解读】
任何行为都会有一个执行者，非谓语动词也不例外，其执行者称作逻辑主语。有的逻辑主语通过特定的语法手段介绍出来，如for sb. to do sth.，one’s doing sth.，one doing sth. 或者by sb.，而有的则是不提自明的“人们”。本句中的buying a car 是动名词短语作主语，它的逻辑主语就是后者，整个意思是“把（人们）购买车辆的时的预算包括在内”。
本句的主要成分是(A significant factor) are the costs，可见主谓人称不一致，应该是(significant factors) are the costs。
7. In 1988 a Soviet icebreaking ship (helped free) three gray whales that (had become trapped) in the Arctic ice after they (had swam) into the coastal waters of Alaska to feed.
这里答案是由had swam改成had swum么能分析下三个括号之间的时态联系吗？
【解读】
swam 是过去式，swum 是过去分词，had 后只能用过去分词。
主句中的helped free 是苏联破冰船发生在过去的行为，had become trapped 和had swum 都是灰鲸发生在helped free 以前的行为。也就是说，灰鲸在被“解救”以前已经被“捕获”，而且是在“游入沿岸海域”是被“捕获”的。
8. Many of the ships used by oceanographic institutions are small (vessels, having outlived their original purpose)
应该是( vessels that have outlived their original purpose) 这个也是通过句子意思判断吗？
【解读】
原句的分词短语having outlived their original purpose是Many of the ships are small的状语，即它的逻辑主语是ships，意思成了“海事部门使用的许多海船是一些小型船，它们都已经超过了原有的设计目的”。答案的that 指代先行词vessels，意思是“海事部门使用的许多海船是已经超过了原有设计目的的小型船”。
原句指海事部门使用的许多海船都已经超过了原有设计目的，其中也包括大型船，而答案中的句子仅指其中的小型船已经超过了原有设计目的。
9. The reason the mammal is the dominant life form in such a wide range of habitats is （its） ability to maintain a steady internal body temperature in practically any environment.
答案E就是没错，为什么REASON is 表语直接用一个事物而非接that +句子
【解读】
◎本句的结构如下：
主句：The reason is (its) ability to maintain a steady internal body temperature in practically any environment.
同位语从句：the mammal is the dominant life form in such a wide range of habitats（美语经常省略引导同位语从句的连接词 that）
◎例句 D 的结构如下：
主句：The shift from traditional to cosmetic dentistry is occuring 由传统牙科到美容牙科的改变正在出现
【主要成分】The shift is occuring
【后置定语】from traditional to cosmetic dentistry
原因状语从句：because adults are getting fewer cavities and becoming more vain 其原因是患龋齿的成人越来越少并且却变得更爱虚荣。
◎例句 A 的结构如下：
主句：The shift from traditional to cosmetic dentistry is
表语从句：because adults are getting fewer cavities and becoming more vain
整个意思变成“由传统牙科到美容牙科的改变是因为患龋齿的成人越来越少并且却变得更爱虚荣”
◎ D 指这种现象正在发生，A指这种现象已经存在。
2 a squadron of 修饰 academicies，原句run-on,he or she用在单数上， for example, everyone needs to take SAT...... 这时候如果后面再指到，everone可以用 he or she,
3.虚拟语气用法自己百度吧，详细，而且主句 will就告诉你什么时态了
如果BY painting的话，就是由 wall发出动作，这个动作只有人发出的，所以 BY painting是错误的。
4。语感而且，sat中 宾语从句一般that不省略
自己买本sat语法书做做，有解析的那种。。
本人12月份考，求祝福
