Hi, Omar Ahmed,
1. "Every citizen must follow the law". - The President said that every citizen......the law.
a. must follow b. had to follow
2. "I must leave now". - Mona said that she ......... leave then.
a. must b. had to c. would have to
3. "I must leave tomorrow". - Mona said that she ......... leave the day after.
a. must b. had to c. would have to
Answers
1. The model answer to this question is "must follow". The test maker says we don't change "must" when we talk about laws! Is this a rule? What is wrong with "b"?
2. The model answer to this question is "had to ". I think "must" is also correct ? Am I right?
3. The model answer to this question is "would have to". The test maker says "must" is changed into "would have to" when we talk about the future. I think both "a" & "b" are correct, too. Am I right?
The book that provides these model answers uses a kind of oversimplification. However, you are right in all your assumptions. Each question here has more than one correct answer. Your assumptions are correct based on the information mentioned on 'A practical English Grammar'. Here's part of it:
325. B 'Must' used for obligation can remain unchanged. Alternatively it can be reported by 'would have to' or 'had to'.
1. I/we must reported by would have to:
'Would have to' is used when the obligation depends on some future action, or when the fulfilment of the obligation appears remote or uncertain, i.e. when must is clearly replaceable by will have to:
'I have just received a letter,' he said. 'I must go home' =
He said that he had just received a letter and would have to go home.
(But had to would be more usual here if he went at once, i.e. had
to-would imply that he went at once.)
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2. I/we must reported by had to:
'Had to' is the usual form for obligations where times for fulfilment have been fixed, or plans made, or when the obligation is fulfilled fairly promptly, or at least by the time the speech is reported:
Tom said, 'I must be there by nine tomorrow' =
Tom said that he had to be there by nine the next day.
'would have to' would be possible here also but would imply that the
obligation was self-imposed and that nooutside authority was involved.
'Had to' could express either an outside authority (i.e. that someone had
told him to be there) or a self-imposed obligation.
All difficulties about had to/would have to can of course be avoided
by keeping must unchanged. In both the above examples 'must' could
have been used instead of had to/would have to.
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3. you/he/they must is reported similarly:
He said, 'You must start at once' =
He said that she must/had to/would have to start at once.
But note that would have to removes the idea of the speaker's
authority:
Tom said, 'If you want to stay on here, you must work harder' =
Tom said that if she wanted to stay on she must/would have to work
harder.
'Must' implies that Tom himself insists on her working harder. 'Would
have to' merely implies that this will be necessary.
