(一)改用“不定式”或“不定式短语”
如果定语从句的时态与主句的时态具有同时性(包括谓语有情态动词)或之后性，则可以用“关系代词或关系副词+不定式”来简化，或直接用“不定式”来修饰先行词。要注意的是，此时的不定式一定要是及物动词，如果是不及物，则需要在动词后面加上相应的介词，使之成为及物动词短语。这个结尾的介词可以提前到关系代词前面，也可以继续留在句尾。前者是正式说法，后者是非正式说法。
例1：We moved to the country so that the children would have a garden in which they could play in.
我们搬到了乡下，好让孩子们有个花园在里面玩。
改为：We moved to the country so that the children would have a garden in which to play.
或者：We moved to the country so that the children would have a garden to play in.
例2：He felt miserable unless he had neighbors (whom)he could quarrel with.
他要是没有可以吵架的邻居就难受。
改为：He felt miserable unless he had neighbors with whom to quarrel.
或者：He felt miserable unless he had neighbors to quarrel with.
例3： The conference which will be held this afternoon is bound to be a great success. 计划在今天下午举行的会议一定会取得成功。
改为：The conference which to be held this afternoon is bound to be a great success.
或者：The conference to be held this afternoon is bound to be a great success.
例4：At a ceremony in Honolulu on Dec. 29, Postmaster General John E. Potter gave a preview of the Lunar New Year Commemorative Stamps Souvenir Sheet, the grand finale of the Lunar Year stamp series, which will be available in 2005.
12月29日，美国邮政总局局长约翰·E·波特在檀香山从句了农历新年的纪念邮票小型张的揭幕仪式，这枚小型张将于2005年正式发行，它为农历新年的系列纪念邮票写下了完美的结局。(注意：与定语从句一样，也可以采用非限制性形式)
改为：At a ceremony in Honolulu on Dec. 29, Postmaster General John E. Potter gave a preview of the Lunar New Year Commemorative Stamps Souvenir Sheet, the grand finale of the Lunar Year stamp series, to be available in 2005.
(二)改用“介词短语”
介词短语替代定语从句有两种方式：(1)省略“关系副词+主语+be动词”，或“关系代词+be动词”;(2)根据从句的意思改编。
例1：We have never forgotten the days (when we were) at college.
我们从来没有忘记在大学对书的日子。
例2：I don’t know the person (who is) in your office.
在你办公司的那个人我不认识。
例3：Those who have high expectations but do not have those relationship skills are likely to be brought down to earth fairly quickly as their Prince or Princess Charming falls off their pedestal.
改为：Those with high expectations but without those relationship skills are likely to be brought down to earth fairly quickly as their Prince or Princess Charming falls off their pedestal.
那些对婚姻期望太高却又不具备处理婚姻关系技巧的人，一旦他们心中的白马王子或白雪公主从神圣的光环里跌落，他们就会很快地回到现实中。
例4：He is not a person who likes to haggle over every ounce.
改为：He is a person above personal interests.
他不是一个斤斤计较的人。
(三)改用“现在分词短语”和“过去分词短语”
“现在分词短语”作后置定语
此项要明白三点：(1)“现在分词短语”与前面的名词一定是主谓关系;(2)它隐含的时态为与谓语动词同一阶段的时态。例如：谓语是一般现在时或将来时，现在分词所隐含的是现在时、现在正在继续时;如果谓语动词为一般过去时或将来时，现在分词所隐含的时态为过去时、过去正在进行时;(3)being+-ed表示“正在进行时的被动语态”。如果信息的中心在什么时候可以用现在分词呢?
(1)当被修饰的名词为“不定代词”、“泛指意义的名词”或“专有名词”，可用现在分句短语作后置定语
由于主语是泛指，句子的意思往往表达的是一条“道理”或一件“事实”，所以它们的隐含时为“一般现在时”，此时就可以用分词短语作后置定语。为了看清分词所隐含的时态，配上定语。
为了读者看得明白，配上定语从句，把分词所替代的时间展示出来。
例1：Anyone touching that wire will get an electric stock.
任何人碰到那根电线就会触电。
= Anyone who touches that wire will get an electric stock.
例2：The only real and lasting solution is to convince people that driving is a skilled taskrequiring (=which requires) constant care and concentration.
唯一一个有效、持久的方法是说法人们相信，开车是一种技术活，需要不断的小心，思想不能开小差。
例3：Charles and Sydney, looking (=who look)so much like each other, are often considered to be twins.
查尔斯和悉尼两个人的相貌非常相似，经常被人误解为双胞胎。
注：虽然被修饰的词是泛指意义的词，但是如果从句里的时态不是同步，则不可以用“现在分词”去作后置定语，只能用“定语从句”。
例句Do you know anybody who has lost a dog?
你知道有谁丢了一只猫?
(2) 当被修饰的名词为特指，即有the限定，可用现在分句短语作后置定语
此类与上面一类一样，与被修饰词之间的关系为主动关系，所不同的是它强调该动词“正在进行”。
例1：Would you help me to pass this note to the person sitting in the corner?
能帮助我把这个条子递给坐在角落的那个人吗?
= Would you help me to pass this note to the person who is sitting in the corner?
注：同上一个“注”道理一样，本项虽然主句的主语是特指，但两个动作时态不是在同一阶段时间内发生，所以也不能用“现在分词”作定语，只能用“定语从句”。
例：The police are questioning the criminal who robbed the bank.
警察在审问那个抢劫银行的犯人。
(4)“Being+过去分词”表示“正在进行时的被动语态”
“Being+过去分词”作后置定语等同于含有“正在进行时+被动语态”的定语从句。请注意与下面的“过去分词”作后置定语的区别，此项里的being是不可以省略的，否定表示现在时、完成时和过去时的被动关系了(详见2)“过去分词”作后置定语)。
例1：The dormitory being built is for girl students.
正在盖的宿舍是给女生住的。
例2：The baby being taken care of by my mother is mine.
正在由我妈妈带的这个婴儿是我的。
“过去分词短语”作后置定语
此项要明白三点：(1)“过去分词短语”与前面的名词一定是动宾关系;(2)主句为一般现在时或一般将来时，“过去分词”所隐含的时态是“一般现在时”或“现在完成时”。如果有时间/地点状语或有by引导的介词，还可以替代过去时，因为时间/地点状语以及by引导的状语都是强调的是动作。当谓语动词是“一般过去时或过去将来时”的时候，“过去分词”所隐含的时态是“一般过去时”或“过去完成时”。下面同样用分词与定语从句对比的方式要看看“过去分词”所替代的时态。
例1：The risk associated with a particular course of action may be lessened by use of a group rather than an individual decision-maker. 对于作出某项行动的决定，集体作的要比个人作的风险小。
= The risk which is associated with a particular course of action may be lessened by use of a group rather than an individual decision-maker. (由于主句为一般现在时，从句的时态与它同步，所以可以省略关系代词和助动词)
例2：In fall 1992, people in Iowa sent truckloads of water to help Floridians hit(=which was hit) by a hurricane.
在1992年的秋天，爱荷华州的居民将好几辆卡车的水送到受飓风袭击的佛罗里达州人的手里。
例3：I’d like to make some comments on the meeting held (=which was held)yesterday. 我想对昨天召开的会议发表一点看法。
(四)改用“形容词短语”
“形容词短语”省略的理由和方式，与“分词短语”作后置定语一样。当它们不是句中的重点信息，就可以去掉关系代词和be动词。形容词作后置定语同定语从句一样，可以分为“限制性”和“非限制性”。
例1：I bought this comic book hot off the press. 我买了这本刚刚出版的漫画书。
例2：She is a kind lady, ready to help others. 她是一个善良的女人, 总是帮助别人。
例3：Companies large and small the world over have been developing their own “corporate universities”. 全世界大大小小的公司都一直在办自己的“公司大学”。
(五)改用“主语从句”或“名词短语”
当which引导的定语从句指代主句全部内容时，可以把which改为it，作形式主语，把原来的主句改成正在主语。或者把定语从句的整个信息改换为名词短语作主语，使原来的定语从句变成简单句。
例4： He indulges himself all day in computer games, which makes his parents extremely sad.
改为：It makes his parents extremely sad that he indulges himself all day in computer games.
他整天沉湎于电脑游戏，这使他父母伤心至极。(主语从句)
或者：His indulgence in computer games all day makes his parents extremely sad. (名词短语)
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