Modal verbs - Ought

This page explains the difficulty of modal verb ought for English language learners.

Ought is a little different from the other modal verbs because it needs to in front of the infinitive, e.g. You ought to tell him. It has several functions but its most common uses seem to be to express some kind of obligation or to make a deduction, as in the following sentences:

  • You ought to do something about your cough. (obligation) You sound awful!
  • He ought to be on the plane by now. (deduction)

It can be used to refer to past obligations or deductions as in the following:

  • You ought to have told him.
  • He ought to have arrived by now.

In all of these sentences, ought to to could be replaced by should with no change of meaning. And in fact, should is more common than ought.


Quiz

Which of the following sentences is correct?

  • I ought to not go
  • I ought not to go.
  • I don't ought to go.
  • I ought to don't go.

The ticked sentence is correct. The others are not possible. (It is interesting that the modal to need , in contrast, allows two forms. Both I don't need to go and I need not go are correct.)

  • I ought to not go
  • I ought not to go. icon
  • I don't ought to go.
  • I ought to don't go.

Modal verb pages