Ought tois a semi-modal verb because it is in some ways like a modal verb and in some ways like a main verb. For example, unlike modal verbs, it is followed byto, but like modal verbs, it does not change form for person:
Iought tophone my parents.
Itought tobe easy now.
Ought to: form
Affirmative
Ought tocomes first in the verb phrase (after the subject and before another verb):
Weought todo more exercise.
Ought tocannot be used with another modal verb:
Medicineought tobe free.
Not:Medicine ought to can be free. orMedicine can ought to be free.
Negative
The negative is formed by adding ‘not’ afterought (ought not to). It can be contracted tooughtn’t to. We don’t usedon’t,doesn’t, didn’twithought to:
Weought not tohave ordered so much food.
Not:We don’t ought to have ordered so much food.
Yououghtn’t tohave said that about his mother.
Not:You didn’t ought to have said that about his mother.
The negative ofought tois not common. We usually useshouldn’torshould notinstead:
Youshouldn’tspeak to your father like that.(preferred toYou oughtn’t to speak…)
Questions
The subject andought tochange position to form questions. We don’t usedo, does, did:
Oughtshetocall the police?
Not:Does she ought to call the police?
Oughtwetobe more worried about the environment?
Not:Do we ought to be more worried about the environment?
The question form ofought tois not very common. It is very formal. We usually useshouldinstead.
Ought to: uses
What is desired or ideal
We useought towhen talking about things which are desired or ideal:
Theyought tohave more parks in the city centre.
Weought toeat lots of fruit and vegetables every day.
We useought to have+ -edform to talk about things that were desired or ideal in the past but which didn’t happen. It can express regret:
Weought to havelockedthe gate. Then the dog wouldn’t have got out.(The ideal or desired thing was that we locked the gate, but we didn’t.)
I often think that Iought to have studiedmedicine not pharmacy.(I would be happier now if I had studied medicine.)
What is likely
We can useought towhen we talk about what is likely or probable:
The concertought toonly take about two hours so we’ll be home by 12 pm.
Thereought tobe some good films at the cinema this weekend.
Ought toorshould?
Ought toandshouldare similar in meaning.Shouldis more common thanought to.Ought tois more formal thanshould:
Thereought tobe more street lights here.(means the same asThereshouldbe more street lights here.)
I reallyoughttowalk my dog more. He’s so fat.(means the same asI reallyshouldwalk my dog more. He’s so fat.)
In speaking, we normally useshouldas a tag for clauses withought to:
Thereought tobe a speed limit here,shouldn’tthere?(preferred toThere ought to be a speed limit here, oughtn’t there?)
Weoughtnot tohave to pay for basic medicines,shouldwe?(preferred toWeought not to have to pay for basic medicines, ought we?)
See also:
Modality: introduction
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