在英语的实际应用中，有时上下文或当时的语境能够帮助我们理解所写的内容，所以有的时候可以省去一个或更多的句子成分，但前提是不影响句子的理解和可读性，因此若有具体的上下文支撑，是可以省去部分成分。 跟定语从句的“瘦身”原理类似，状语从句也可以“瘦身”，这种“瘦身”原理就是省略。若从句的主语与主句的主语一样，那么通常可以省略从句的主语或助词，然后动词做相应的变化，例如：While Sarah was studying, she fell asleep.萨拉在学习时睡着了。解析：此句可以省略，因为从句中的主语和主句中的主语都是 Sarah，因此可以省略为 While studying, she fell asleep，但是以下这句不能省略，例如：While Sarah was talking, I fell asleep.萨拉说话的时候，我睡着了。解析：从句中的主语 Sarah 和主句的主语 I 不一样，所以不能省略。一、状语从句带 be 动词的省略在带 be 动词（am, is, are, was, were, been, being）的状语从句中，直接省略主语和 be 动词，例如：1. 萨拉在学习时睡着了。While she was studying, Sarah fell asleep.省略：While studying, Sarah fell asleep.2. 尽管他迟到了，他还是被允许去看电影。Although he was late, he was admitted to the movie.省略：Although late, he was admitted to the movie.二、状语从句不带 be 动词的省略 在不带 be 动词（am, is, are, was, were, been, being）的状语从句中，直接省略主语，然后把对应的动词变成 -ing 形式，例如：1. 杰克读完这本书后，把它放回书架上。After he finished the book, Jack put it back on his shelf.省略：After finishing the book, Jack put it back on his shelf.2. 在去火车站之前，玛丽亚要核对一下火车时刻表。Before she goes to the train station, Maria will check the train schedule.省略：Before going to the train station, Maria will check the train schedule.
三、 while 引导的状语从句的省略1. 当 while 引导的时间状语从句以 while 开头，且表示主从句的动作同时发生时，while 从句用进行时，那么省略规则跟其他带 be 动词的从句一样省略主语和 be 动词，就是去掉主语和 be 动词，例如： 当他们骑自行车时，学生们看见一个马戏团进城来。While they were riding their bikes, the students saw a circus coming into town.省略：While riding their bikes, the students saw a circus coming into town.此时的 while 也可以一起省略，比如上面省略后的例句还可以进一步省略：While riding their bikes, the students saw a circus coming into town.省略：Riding their bikes, the students saw a circus coming into town.2. 当 while 引导的时间状语从句出现在句中时， while 就不能再省略了，例如：学生们骑自行车时看到一个马戏团进城。The students saw a circus coming into town while riding their bikes.❌: The students saw a circus coming into town riding their bikes.3. 当 while 引导让步状语从句时，首先要保留 while 和去掉从句中的主语，若从句中有 be 动词，则去掉 be 动词保留名词或形容词，此时的 while 不能省略，例如：虽然他是一个快乐的人，但他有许多严重的问题。While he was a happy man, he had many serious problems.省略：While happy, he had many serious problems.四、as，since，because 引导的原因状语从句的省略1. 这三个连词引导的从句的省略规则是一样的，就是直接去掉连词和主语，然后对应的动词用 -ing 形式，例如：因为他迟到了，所以他开车去上班。Because he was late, he drove to work.省略：Being late, he drove to work.因为她累了，所以睡得很晚。Since she was tired, she slept in late.省略：Being tired, she slept in date.由于汤姆有额外的工作要做，因此他工作到很晚。As Tom had extra work to do, he stayed late at work.省略：Having extra work to do, Tom stayed late at work.2. 当从句中的动词是否定形式时，要在省略后动词的 -ing 形式前面加 not，例如：由于他不想打扰她，因此他很快离开了房间。As he didn't want to disturb her, he left the room quickly.省略：Not wanting to disturb her, he left the room quickly.因为她不明白这个问题，所以她请老师帮忙。Because she didn't understand the question, she asked the teacher for some help.省略：Not understanding the question, she asked the teacher for some help.五、As，before，after，since，when 和 as soon as 引导的时间状语从句1. before，after 和 since 这几个连词引导的从句的省略规则都是：保留时间连词，去掉主语，把动词变成 -ing 形式或用名词，例如： 他考试后睡了很长时间。After he took the test, he slept for a long time.省略：After taking the test, he slept for a long time. （-ing 形式）省略：After the test, he slept for a long time. （名词）自从我搬到罗切斯特，我去了爱乐乐团无数次。Since I moved to Rochester, I have been to the Philharmonic numerous times.省略：Since moving to Rochester, I have been to the Philharmonic numerous times.2. as 引导的从句的省略规则是：去掉 as 和主语和 be 动词，把动词变成 -ing 形式，此时跟 while 引导的时间状语从句类似，表示主从句动作同时发生，例如：当我睡着的时候，我想起了我在意大利的朋友们。As I was falling asleep, I thought about my friends in Italy.省略：Falling asleep, I thought about my friends in Italy.她开车去上班时，看见路上有一只鹿。As she was driving to work, she saw a deer in the road.省略：Driving to work, she saw a deer in the road.3. as soon as 引导的从句的省略规则是：用 upon 或 on 代替 as soon as，去掉主语，把动词变成 -ing 形式，例如：她一写完报告就把它交给了老板。As soon as she finished the report, she gave it to the boss.省略：Upon finishing the report, she gave it to the boss.我们一醒来，就拿着钓竿到湖边去了。As soon as we woke up, we got our fishing poles and went to the lake.省略：On/Upon waking up, we got our fishing poles and went to the lake.4. when 引导的时间状语从句省略规则1. 在表达主从句动作先后发生时，省略规则跟 as soon as 类似，用 upon 或 on 代替 when，去掉主语，把动词变成 -ing 形式，例如：桑德拉大学毕业后申请了一份工作。When Sandra graduated from university, she applied for a job.省略：On/Upon graduating from university, she applied for a job.2. 当表达主从句的动作同时发生时，省略规则跟 while 引导的时间状语从句类似，省略主语和 be 动词，例如：当你晚上独自在巴黎的街道上行走时，要小心。When you are walking alone at night in Paris streets, be careful.省略：When walking alone at night in Paris streets, be careful.3. 在被动语态或从句中含有 be 动词时，可以省略从句的主语和 be 动词，例如：他小时候很淘气。When he was a little boy, he was very naughty.省略：When a little boy, he was very naughty.如果单词或短语使用太频繁，可能会失去其价值。When they are used too often, words or phrases may lose their value.省略：When used too often, words or phrases may lose their value.
