(4)先行词同时包括人和物时，只能用他和她，
例如：Lu Xun and his works that we are familiar with are considered great.
6. 只能用which不能用that的情形
(1)当非限制性定语从句中的先行词指物时，只能用which
例如：The pencil-case, which I bought last week, is missing.
(2)关系代词前面有介词时，只能用which
例如：The tree under which we used to take a rest has been cut down.
(3)先行词本身就是that时
例如：I don’t like that which he did.

关系副词的用法 
1. when的用法：它的先行词通常是time, day, morning等。有时也可和一些介词一起引导定语从句。
例如：Do you remember the time when she went abroad?
2. where的用法：它的先行词通常有place, spot, room等。
例如：I like places where the weather is always warm.
3. why的用法：它的先行词只有reason。Why时常也可以省略。
例如：Tell me the reason why she was late.

考点名称：固定搭配

• 固定搭配：
  英语中的固定搭配主要是指英语中的习惯用法，如有固定用法的一些动词短语、介词短语、名词词组及形容词词组。
  例如：
  take part in (参加) 
  by accident (偶然地) 
  lucky dog (幸运儿)
  be interested in (对…感兴趣)

• 初中英语常见固定搭配：
  (一)加-ing
  enjoy / like doing sth 喜欢做----    
  spend....(in) doing sth 在做---花费---  
  try doing 试着做------                
  be busy doing sth 忙于做------
  finish doing sth 完成做----           
  look forward to + doing sth 期待做----(现在进行时)
  be doing 正在做---     
  Thank you for (doing) sth 为了--感谢你

  （二）加-to
  decide to do sth 决定去做-----             
  ask (sb)to do 要求(某人)去做----      
  It’s+adj +to do sth . 做---(怎么样)        
  would like / want to do 想要做-----    
  It takes sb sometime to do sth在做----花费----
  
  （三）加原形
  let / make sb do sth 让某人做某事   
  be going to / will do sth （一般将来时态）
  
  （四）加-to 或-ing意思不同
  forget doing 忘记做过了-----(已做)    
  forget to do 忘记去做------(还没做)   
  remember doing记得做过了-----(已做)
  remember to do记得去做------(还没做)
  
  （五）加-to 或-ing意思相同
  begin / start to do sth = begin / start doing sth开始做------
  
  （六）
  A）动词+ 介词
  agree with同意....的意见(想法)；符合    
  help ... with ...帮助(某人)做(某事)  listen to听...              
  ..get to到达....       
  fall off (从......)掉下base on以....(为)根据     
  knock at /on敲(门、窗)        
  laugh at嘲笑
  learn.. from 向...学习     
  live on继续存在；靠...生活 
  look after照顾，照看look at看；观看           
  look for寻找             
  look like看起来像
  pay for (sth.)付钱；支付 
  point at指示；指向          
  point to指向....prefer to ...宁愿(选择);更喜欢           
  quarrel with (和某人)吵架
  regard...as ...把....当作....；当作                 
  stop...from阻止.....做.....
  talk about说话；谈话；谈论                        
  talk with与......交谈think about考虑                                  
  think of认为；想起
  B)动词+ 副词                                                     
  ask for请求；询问       
  carry on坚持下去；继续下去     
  cut down砍倒 
  clean up清除；收拾干净  
  come down下来；落    
  come along来；随同
  come in进来            
  come on来吧；跟着来；赶快 
  come over过来；顺便来访           
  come out出来；出现；(花)开；发(芽)      
  drop off放下(某物)；下车                              
  eat up吃光；吃完
  fall behind落在......后面；输给别人            
  fall down跌倒；从......落下
  find out查出(真相)                                
  get back回来；取回
  get down下来；落下；把......取下来             
  get off下来；从......下来get on上(车)               
  get up起床                
  give up放弃go on继续               
  go out出去     
  go over过一遍；仔细检查
  grow up长大；成长      
  hand in交上来                
  hurry up赶快
  hold on (口语)等一等；(打电话时)不挂断             
  look out留神；注意
  look over (仔细)检查                            
  look up向上看；抬头看  
  pass on传递；转移到....                          
  pick up拾起；捡起
  put away放好；把....收起来  
  put on穿上；戴上；(戏剧等)上演；放(唱片等
  put down把(某物)放下来                             
  put up挂起；举起
  run away流失；逃跑；逃走 
  rush out冲出去 
  set off出发；动身；
  启程send up发射；把......往上送  
  shut down把......关上      
  sit down坐下
  slow down减缓；减速      
  take off脱掉(衣服)          
  take out取出
  throw about乱丢；抛撒