定语从句中关系词的省略与不省略

　　1.关系代词which,whom,who,that在定语从句中作宾语时可以省略.

　　Hereistheman(who/that/whom)you'rebeenlookingfor.

　　以下情况不能省略：

　　（1）在介词+whom与介词+which中,whom,which不能省略.

　　DoyouknowanyshopsnearbyinwhichIcanbuyflowers?

　　Thatistheheadmasterwithwhommyfatherwastalkingjustnow.

　　注：当介词放在动词后时,which,whom就可以省略.

　　Whoistheman(whom)youtalkedwithjustnow?

　　（2）在非限制性定语从句中,作宾语的关系代词也不能省略.

　　MrGreen,whomyouknow,isthetallestinourschool.

　　Theelephantislikeaspear,asanybodycansee.

　　（3）在thesame...as,such...as,as...as,thesame...that中,as,that即使作宾语,也不能省略Ihaveboughtthesamebicycleasyouhave(bought).(指同类用as)

　　ThisisthesamebookthatIreadthedaybeforeyesterday.(that指同一个)

　　（4）当由and,but,or等连词连接两个或两个以上的定语从句修饰一个先行词时,第一个关系代词可省,但第二,第三个不可省略.

　　Thisisthebook(which)IreadyesterdayandwhichIfindveryinteresting.

　　2.当that在从句中作补语时可以省略.

　　Heisnottheman(that)heusedtobe.

　　Sheisall(that)ateachershouldbe.

　　3.在therebe结构中出现定语从句,或在定语从句中出现therebe时,用作主语的关系代词也可省略.

　　Thereisamandownstairs(who)wantstoseeyou.

　　Thisisthebestdictionary(that)thereisinthelibrary.

　　4.状语的省略

　　（1）当先行词是reason,而且定语从句中作原因状语时,关系代词可用why,that,也可以省略.

　　Thereason(why/that)hefailedwashislaziness.

　　Thatisthereason(why)Ididit.

　　（2）当先行词是way,且在定语从句中作方式状语时,关系代词可用inwhich,that,也可以省略.

　　Theway(inwhich/that)thesecomradeslookatproblemsiswrong.

　　Thatwastheway(inwhich/that)sheworkedtheproblemout.

　　注意：当关系代词在定语从句中作主语时,不省略.

　　例如：Idon'tknowthewaythat/whichleadstothetopofthemountains.

　　(3)当先行词是time时,关系代词可用when,that或省略.

　　Thesecondtime(that)Isawhimwasin1980.

　　Idon'tknowtheexacttime(when/that)thesportsmeetwilltakeplace.

　　注意：关系代词作宾语有时也不能省略.

　　希望能够帮助楼主