English verb conjugation
OUGHT TO INTERVENE

Regular verb: intervene - intervened - intervened

Affirmation

Simple form	V-ing form
I ought to intervene you ought to intervene he ought to intervene we ought to intervene you ought to intervene they ought to intervene	I ought to be intervening you ought to be intervening he ought to be intervening we ought to be intervening you ought to be intervening they ought to be intervening
Perfect	V-ing perfect
I ought to have intervened you ought to have intervened he ought to have intervened we ought to have intervened you ought to have intervened they ought to have intervened	I ought to have been intervening you ought to have been intervening he ought to have been intervening we ought to have been intervening you ought to have been intervening they ought to have been intervening

Negation

Simple form	V-ing form
I oughtn't to intervene you oughtn't to intervene he oughtn't to intervene we oughtn't to intervene you oughtn't to intervene they oughtn't to intervene	I oughtn't to be intervening you oughtn't to be intervening he oughtn't to be intervening we oughtn't to be intervening you oughtn't to be intervening they oughtn't to be intervening
Perfect	V-ing perfect
I oughtn't to have intervened you oughtn't to have intervened he oughtn't to have intervened we oughtn't to have intervened you oughtn't to have intervened they oughtn't to have intervened	I oughtn't to have been intervening you oughtn't to have been intervening he oughtn't to have been intervening we oughtn't to have been intervening you oughtn't to have been intervening they oughtn't to have been intervening

Interrogative form

Simple form	V-ing form
ought to I intervene? ought to you intervene? ought to he intervene? ought to we intervene? ought to you intervene? ought to they intervene?	ought to I be intervening? ought to you be intervening? ought to he be intervening? ought to we be intervening? ought to you be intervening? ought to they be intervening?
Perfect	V-ing perfect
ought to I have intervened? ought to you have intervened? ought to he have intervened? ought to we have intervened? ought to you have intervened? ought to they have intervened?	ought to I have been intervening? ought to you have been intervening? ought to he have been intervening? ought to we have been intervening? ought to you have been intervening? ought to they have been intervening?

Interro-negative form

Simple form	V-ing form
oughtn't I to intervene? oughtn't you to intervene? oughtn't he to intervene? oughtn't we to intervene? oughtn't you to intervene? oughtn't they to intervene?	oughtn't I to be intervening? oughtn't you to be intervening? oughtn't he to be intervening? oughtn't we to be intervening? oughtn't you to be intervening? oughtn't they to be intervening?
Perfect	V-ing perfect
oughtn't I to have intervened? oughtn't you to have intervened? oughtn't he to have intervened? oughtn't we to have intervened? oughtn't you to have intervened? oughtn't they to have intervened?	oughtn't I to have been intervening? oughtn't you to have been intervening? oughtn't he to have been intervening? oughtn't we to have been intervening? oughtn't you to have been intervening? oughtn't they to have been intervening?