if和whether在名词性从句中的用法.ppt

1、如果在名词条款中使用A、1、if和whether，则A、2、whether和if都可以用作连接词，并引导名词子句以表示“是”。区别在于，whether可以引导任何类型的名词子句。If只能指导对象条款和主题条款。A，3，宾语从句，诱导宾语从句whether和if都可以使用，两者都经常交换。Whether在正反两方面提问和选择的意义很强，常用在形式文体上；If主要用于口语，he asked me whether/if I could lend him my bike。could you tell us whether/if it snows in winter in Australia？she a

2、sked them whether/if they had gone there by car or by train .a、4、1。介词后仅用whether引导宾语从句。this depends on whether we are determined to do it .I am not interested in whether youll comor not .im thinking about whetherer well have a meeting。4点例外、A、5，2。和四物动词discuss、consider等后面的宾语从句中只能使用whether。wediscussed w

3、hether weshould make a change in our plan . web were discussing whether weshould take some measures . were discussing whether well go on a、a、6、3。将宾语从句放在文章的开头强调时，只应使用whether。Whether it is true or not，I cant tell . whether you have met George before，I cant remember。a、7、4。引导否定宾语从句，只使用if。Whether不能用于引导否定

4、宾语从句。因为积极和消极选择的意义更强。sheasked me if Tom did nt come . he considered if he should nt tell her the secret .a，8，whether/if guide object子句，通常换徐璐(4点除外)，只使用whether discuss等监护宾语从句放入句子的第一个表，如if:介词后否定宾语从句指南，a，thank you，But _ _ _ _ _ _ ill be free I m not sure at the moment . a . while b . if c . when 2-what a

5、re you anxious about？-_ _ _ _ _ _ _ _ _ _ _ _ A . if we succed b . that we can succed c . do we succeed . whether we can succed引导主语，在句子开头只使用whether。Whether we go there is not decided。its doubtful whether/if there ll be any seats left。a，11，指示标语子句时仅使用whether。what we want to know is whether he will com

6、e to speak to us tomorrow .the doubt was whether you had broken the beautful vase。the question is whether We can get there on time。表语子句，A，12，在引导同文语子句时仅使用whether。the question whetherewell build another lectire building hant been setled。the question whether hell is unknown。we must consider the questio

7、n Whether we will take these measures。同级子句、A、13、Exercises、1。the question has not been answer red _ _ _ Taiwan will be included on the Olympic torch relay route .a that c which dif 2 ._ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ theyll go to the summer palace _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _Depends on B. W

8、hetherDepends upon C. WhetherDepended on D. IfDepended upon、Bwhether、A、14，1。直接与or not连接时，仅使用whether。I dont know whether or not he will go .im not sure whether or not they will come for our help .注意如果whether和or not没有连接，可以在口语中用if替换whether。示例：I am not certain whether/if the train will arrive on time or

9、 not。I dont care whether/if your car breakdown or not .其他情况(3点)、A、15，2。动词不定式之前只能使用whether。He doeson know whether to stay or not .she doess nt knows whether to get married now or wait .a、16、3。如果if导致模糊，请仅使用whether。If除了引导宾语从句外，还可以引导条件状语从句到“如果”。please let me know if you intent to come . a:if刘涛宾语从句，“请告诉我你想不想来。B: if指导条件状语从句，“来的话请告诉我。”please let me know whether you intent to come . ex : let me know if he has left for Shang hai。请告诉我他已经去上海了。如果他已经去了上