Student or Learner
What is the difference between 'You ought to be home early' and 'You must be home early'?
Thank you in advance.
NOT A TEACHER
(1) I understand how difficult it is to understand these little words.
(a) Many times "ought to" = "should" (good idea).
(b) Many times "must" = "have to" (100% necessary).
(2) Let's say that you are driving a car. When you see a red light,
you must stop (because that's the law and because if you do not stop,
a car coming through the intersection may hit your car and you may die).
(a) If you use "ought to/should" in that sentence, then the sentence would
mean: If you want to stop, that's fine, but if you do not stop, that's no
big problem. Of course, it is a big problem, so you must/have to stop at
every red light.
Ought to is used to talk about obligation and duty, to give advice and to say what we think it is right for people to do or have done.
Must has similar meaning to ought to but is stronger or more definite.
You ought to be home early.
(a piece of advice which may or may not be followed.)
You must be home early.
(an order which is likely to be obeyed)