[Grammar] ought to/ should

[Venus.jam]

hi

I know that there is a difference in meaning between should and ought to, that is should is used to refer to an idea (you should see this movie). But, ought to is used when there will be some bad consequences (you ought to study for the exam). However, I wonder if the same difference exist when we make use of "ought to/ should" in expressing degrees of certainty in the future time as in "you should do well on the test" and "you ought to do well on the test". Is there any difference between these two forms?

 

[Venus.jam]

I see. Would you please answer the questions below:

1. could you please let me know in what situations "should" cannot be replaced by "ought to"?

2. Do you mean that we cannot use "should" when we want to refer to someone's responsibility or duty?


3. what about this sentence "you ought not park your car here. As "ought not" is not common can we replace it by "should not" in this sentence? But, what if a policeman want to tell the same statement. I think "should" does not show warning. Does the policeman say "you had better not park your car here?"

 

[GoesStation]

3. What about this sentence? "You ought not to park your car here. As "ought not" is not common can we replace it by "should not" in this sentence? But, what if a policeman wants to say [STRIKE]tell[/STRIKE] the same statement. I think "should" does not show warning. Does the policeman say "you had better not park your car here?"

An American police officer would probably say You can't park your car here. From what I understand, a British policeman would say What's all this, then?​

 

[Raymott]

"2. Do you mean that we cannot use "should" when we want to refer to someone's responsibility or duty?"

I can't find any way that he could have meant that. How did you infer that?

 

[Venus.jam]

He said "should cannot always be replaced by ought to". Thus, I just inferred it from what I'd read from a grammar book which says Should and ought to both express advisability. Their meaning ranges in strength from a suggestion (this is a good idea) to a statement about responsibility or duty (This is a very important thing to do).

 

[Raymott]

Sorry, I'm lost. But it's not important.

 

[tzfujimino]

He said "not always", Venus.jam.
He meant 'should' can sometimes be replaced by 'ought to', but not always.


(Edit)
After I read your post #3 again, you seem to understand what 'not always' means.