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Longman Dictionary of Contemporary English
ought to
modal verb
EXAMPLES FROM OTHER ENTRIES
▪ Don't you think you ought to eat before you go?
▪ Maybe we ought to call the doctor.
▪ The berries ought to be ripe by now.
▪ Tricking old people like that ought to be illegal.
▪ We ought to be able to find someone to do the job pretty quickly.
▪ You ought to email or call her and say you're sorry.
▪ You really ought to apologize to her, you know.
EXAMPLES FROM CORPUS
▪ I believe women ought to be ordained to the priesthood.
▪ If there is not tension at the Times around this issue, there ought to be.
▪ In the genre terms, that ought to have made him unassailable.
▪ She ought to have recognized Harry, that woollen hat, the jacket.
▪ They can just be people who believe they ought to reshape society from top to bottom.
▪ Tom Ripley ought to write the letter, he thought.
▪ You ought to be proud, Herb.
Wiktionary
ought to

vb. 1 (context auxiliary English) (non-gloss definition: Indicating duty or obligation.) 2 (context auxiliary English) (non-gloss definition: Indicating advisability or prudence.) 3 (context auxiliary English) (non-gloss definition: Indicating desirability.) 4 (context auxiliary English) (non-gloss definition: Indicating likelihood or probability.)

Usage examples of "ought to".

But I tell you as an engineer what you ought to know better than I do, that sort of work is no more related to unbinding locks and stealing vehicles than a minestrone is to a manticore.

It occurred to me that maybe I ought to find a place where I could hide in case someone came upstairs.

Sometimes he wondered if he ought to believe so peculiar a story, but he did find the details titillating.

I looked back at Shiara and opened my mouth to ask why we ought to leave, but I stopped before I said anything.

He ought to be ready to die here if what he'd been saying was true.