I must get my haircut.
tdol said:Try putting sentence 1) into the negative and your analysis breaks down. Because 'oughtn't is not to 'shouldn't' as 'don't have to' is to 'mustn't'.
One example of 'must' doesn't conclude much about modality:
This could have many different meanings.
How are you defining modality?
Many grammarians say 'ought' is a modal', so your initial claim that it technically isn't a modal was inaccurate as it is a statement of opinion rather than a generally accepted fact. 'Ought' regularly appears in lists of modals.
If you want to argue that it isn't, I'm fine with that, but I haven't seen anything here to change my view yet.
1) Are modals verbs? Or just tools to express nuances?
"I came, I saw, I conquered" (Julius Ceasar)
Is the meaning of this sentence clear? Perfectly.
"Some say they can, some say they can't
some say they will, some say they won't" (Lyrics from "Boredom", a Procol Harum song from the sixties)
What is this guy singing about? Is the meaning clear without a verb after the modals?
I don't see why it would be much simpler- the only issue is the use of the infinitve marker. I'm not even saying it is important to say it is a verb. This discussion started because I disagreed with the assertion that it is technically not a modal verb. On a learner's site, where most will have dutifully looked in Michael Swan and seen that he calls it a modal, it might be a bit confusing to make such an assertion without qualifying it as an opinion, not a technical truth.2) Why is it so important to consider "ought" as a modal? It would be much simpler if it were not.
It is really true that no two modal sentences can be synonymous if the verb is different? Hmm, possibly, but, then again, possibly not.In any given sentence, if you replace a modal with another, you change the meaning.
"You may be right" is not the same as "You could be right" or "You might be right".
Some feel that ought to can carry a more critical or hectoring tone, so they can distinguish them, but this would only be in some cases, and would normally be in spoken forms where tone of voice could be used.Is there a difference in meaning between "You should come" and "You ought to come"?
A difference comparable to the one between "You needn't come" and "You don't need to come"?
In my opinion, there is one: in each pair, the first sentence is "modalised", the second is not -- the speaker does not express his/her personal point of view.
Why not? There's no rule against duplication.If there is no difference in meaning, why 2 modals to express the same idea?