[学习方法]宾语从句注意事项

宾语从句中that不能省略的情况：  一、句中的动词后接两个或两个以上的that从句作宾语时，第一个that可省，但后面的that 不可省。如：
 He said (that) he couldn’t tell you right away and that you wouldn’t understand.  二、当主句的谓语动词与that宾语从句之间有插入语时，that一般不可省。如：
 Just then I noticed, for the first time, that our master was wearing his fine green coat and his black silk cap.
 三、当that从句是双宾语中的直接宾语时，that不可省。如：        I must never tell anyone that I could not see the cloth.
 四、当that宾语从句前有it作形式宾语时，that 不可省。  I find it necessary that we should ask him for his advice. 宾语从句的时态
 一、主句谓语动词是现在时或将来时，从句谓语动词可以用任何所需要的时态。  He says his father is/was a teacher.  I’m sure that you’ll succeed.
 二、主句谓语动词是过去时态，从句谓语动词一般须用过去时。  He said he was watching TV.
 They didn’t know when they would go to Beijing.  She said she had finished the work..  注：从句如果与某一具体的过去时间状语连用，尽管其谓语动作发生在主句谓语动作之前，
仍用一般过去时。
 She told me that her father died in 1991.
 三、从句所说明的是一般真理或客观事实，即使主句用过去时，从句仍用一般现在时。  The teacher told the students that the computer is a wonderful machine. 1，名词性从句的语序
 名词性从句在句子中，除了关联词在从句之首外，其它部分则和陈述句语序相同，而同学们在学习中最容易把它当成疑问句语序，特别是以wh-引起的名词性从句。  （1）We don't know when will she come.(误)     We don't know when she'll come. (正)
 （2）How will the book sell depends on its writer. (误)    How the book will sell depends on its writer. (正)  （3）Who the accident caused is a complete mystery.(误)    Who caused the accident is a complete mystery. (正)  2，名词性从句中虚拟语气的使用
 1) 在动词suggest，insist，order，advise， require，desire等后的宾语从句中，谓语用虚拟语气。
 The teacher suggested we（should）carry out the experiment in time．  I insisted that you（should）be there on time．  注：当suggest表“暗示、表明”，insist表“坚持认为”时，用陈述语气。  His pale face suggested that he was ill．
 He insisted that he heard someone in the next room．
 2）在advice，suggestion，order等名词后的表语从句或同位语从句中，也应用虚拟语气。  His advice is that we（should）go to the cinema tonight．（表语从句）  The order that the work（should）be started at once has been given．（同位语从句）
3，Whether 与 If   的使用    1）Whether与if的相同点
  一、whether与if均可引导宾语从句，可替换。
I asked the teacher whether／if it was true．我问老师这是否是真的。
  二、whether与if都可引导主语从句，whether从句可放在句首或句末；而if从句一般放在句末。
whether they wi11 come is unknown．＝It is unknown whether／if they'll come.   三、在be + 形容词之后，如：
  He was not sure whether(if) it is right or wrong.  2）只用whether，不用if的情况  一、引导表语从句。如：
 The question was whether Tom has gone to Shanghai.  二、引导同位语从句。如：
 The problem whether it is right or wrong has not yet been discussed.
 we ought to discuss the question carefully whether we'll attend the meeting or not  三、用作介词宾语（介词往往可以省略）。如：  It all depends on whether they'll help us.    四、和不定式连用。如：
 Please tell me whether to go there.  
 五、与or not连用，引导状语从句，表示"不管与否"、"不论与否"之意。如：  The meal will be ready for her whether she comes or not．
 六、与or连用，构成句型"whether...or„"意为"不管„„还是„„"。如：  Whether he will come himself or send a person is unimportant。   七、宾语从句位于句首(起强调作用)时。如：  whether they can help us，I don't know yet．  
  八、在主语从句中，只有用it作形式主语时，whether和if都可用，否则，只用whether   Whether we shall attend the meeting hasn't been decided yet.  It hasn't been decided whether(if) we shall attend the meeting.   九、引导让步状语从句，只能用whether。如：  Whether you like it or not, you must do it well.   十、 用if 引起歧义时。如：  Please let me know if you like it.  3）只用if不用whether的情况  引导否定形式的宾语从句。如：  I don't care if he doesn't come．