Ought To

Ought is a modal auxiliary verb. There is no –s in the third person singular.

Ought is different from other auxiliary verbs. It is used with to

Note that to is dropped in question tags.

Ought does not have infinitives (to ought) or participles (oughting, oughted). Questions and negatives are made without do.

Ought is rarely used in questions and negatives; should is generally used instead. A structure with think … ought is also common.

Ought: Meaning

Ought expresses duty, necessity, desirability and similar ideas. It is often used to advise people – to tell them that they have a duty to do things. The meaning is similar to should

Ought is not as forceful as must.


To express probability

Ought can express logical probability.

Ought to have + past participle

When ought refers to past time, it is followed by the perfect infinitive. This structure can be used to talk about things which were supposed to happen but did not.

This structure can also be used to make guesses.

Ought not to have can be used to talk about things that happened unnecessarily.