ought to

The verb ought to only exists in simple present and present perfect forms.
Examples:

• Helen ought to be more careful.
  
• I ought to stay in bed.
  
• They ought to be here already.
  
• You ought to eat more vegetables.
  
• Tom ought to take her home.
  
• It ought to work properly.

  The forms of ought to:

All persons	Present	Present perfect
Affirmative	ought to	ought to have
Negative	ought not to,  oughtn't to	ought not to have,  oughtn't to have