must直接引语改间接引语问题。

"Must i stay in bed the whole day?"the man asked
改成ha asked if he must stay in bed the whole day对吗。正确答案用的是had to。why why？

其实这道题是一道挺简单的题，两个要从意思上判断的
例如must就是这个人义务中所要做的，可以是自己主观想要做或是不得不做的东西。
而 have to就只是这个人不得不做的东西了。
原句中have to是不能用来当疑问词的，只能用 do I have to........
而到了间接引语中，以第三者的口吻来叙述是，就代表这个人在问是不是自己不得不呆在家里了。
如果还不清楚就追加提问吧。

引述别人的话有两种方式：一是使用引号引出人家的原话，这叫做直接引语；一是用自己的话把人家的话转述出来，这叫做间接引语。例如： john said, "i'm going to london with my father." 约翰说："我要和父亲到伦敦去。"（引号内是直接引语） john said that he was going to london with his father. 约翰说，他要和他父亲去伦敦。（宾语从句是间接引语） 由直接引语变为间接引语，分以下情况： 1． 直接引语是陈述句时 间接引语为that引导的宾语从句（口语中that可以省略），主句的引述动词主要有say ,tell, repeat, explain, think等。 he said , "you are younger than i."-'he said (that ) i was younger than him. 2.直接引语是疑问句时 间接引语为陈述语序：主句的谓语动词say 改为ask,或改为wonder, do not know, want to know, be not sure, be puzzled等。 （1） 一般疑问句或反意疑问句变为if (whether)引导的宾语从句。 she said, "do you often come here to read newspapers?" →she asked me if (或whether)i often went there to read newspapers. she asked me , "you have seen the film, haven't you?" →she asked me whether(或if )i had seen the film. （2） 选择疑问句变为whether….or 宾语从句。 i asked him, "will you stay at home or go to a film tonight?" →i asked him whether he would stay at home or go to a film that night. (3)特殊疑问句变为由原来的疑问词引导的宾语从句。 he asked , "where do you live?" →he asked me where i lived. 3.直接引语是祈使句时 间接引语为不定式，作ask , tell, beg, order, warn, advise等动词的宾语补足语（don't 变为not ）. the teacher said to the boy, "open the window."→the teacher told the boy to open the window. his father said to him , "don't leave the door open."→his father told him not to leave the door open. [注意] （1） 有些表示建议、提议、劝告或要求的祈使句，可以用suggest ,insist等动词 加以转述。例如： he said, "let's go to the theatre." →he suggested (our )going to the theatre.或he suggested that we(should) go to the theatre. (2) "would you mind opening the window?" he asked. →he asked me to open the window. "why don't you take a walk after supper?" he asked . →he advised me to take a walk after supper. "shall we listen to the music?" he asked. →he suggested listening to the music. 4.直接引语是感叹句时 间接引语为what 或how 引导，也可以用that 引导。 she said, "what a lovely day it is !" →she said what a lovely day it was .或she said that it was a lovely day. 5．如果主句谓语动词为各种现在时或一般将来时，则间接引语中的动词仍保持直接引语原来时态。如果主句谓语动词为过去时，间接引语中的动词时态按下列变化： （1） 一般现在时变为一般过去时 （2） 现在进行时变为过去进行时 （3） 一般将来时变为过去将来时 （4） 现在完成时变为过去完成时 （5） 一般过去时变为过去完成时 （6） 过去完成时不变，仍为过去完成时 [注意] （1） 如果直接引语是表示客观真理时，变为间接引语，一般现在时不改为一般过去时。如： the teacher said "the earth goes round the sun." →the teacher said that the earth goes round the sun. （2） 如果直接引语中有明确表示过时间的状语，变为间接引语时，一般过去时不改为过去完成时。如： he said to me, "i was born in 1973." →he told me that he was born in 1973. (3)如果直接引语所述事实在当时和目前同样生效，变为间接宾语时，一般现在时不改为一般过去时。如： he said, "i'm a boy, not a girl." →he said that he is a boy ,not a girl. (4)如果直接引语中的谓语动词表示一种反复出现或习惯动作，在变为间接引时，一般现在时不改为一般过去时。如： the girl said, "i get up at six every morning." →the girl said that she gets up at six every morning. (5)如果直接引语中含有since, when, while 引导的表示过去时间的状语从句，在变为间接引语时，只改变主句中的谓语动词，从句的一般过去时则不变。如： he said to me, "i have taught english since he came here ." →he told me that he had taught english since he came here. (6)如果直接引语中含有情态动词 must, need, had better以及情态动词的过去式could, might, should, would,在变为间接引语时，这些情态动词没有时态的改变。例如： the teacher said to me . "you must pay more attention to your pronunciation." →the teacher told me that i must (have to ) pay more attention to my pronunciation. he said , "i could swim when i was only six ." →he said that he could swim when he was only six. 6.代词等一般地应作用相应的变化，变化方法见下表。 指示代词 this……these these……those 表示时间的词 now……then today……that day this week(month ,etc)……that week (month ,etc) yesterday……the day before last week(month ,etc)……the week(month ,etc) before three days (a year ,etc) ago……three days (a year. etc) before tomorrow……the next (following ) day next week (month ,etc)……the next (following ) week (month ,etc) 表地点的词 here……there 动词 bring……take come……go 希望能够帮到楼主